47 Chapter 47 — COVID-19 and Endocrine Disorders（COVID-19 與內分泌疾病）

本章定位：Williams 15e 把 COVID-19 對內分泌系統的影響整合在「acute infection + 治療相關 + 疫苗副作用 + Long COVID（PASC）」四軸 framework——這是 2020-2024 endocrinology 最重磅新增章節。對 fellow 而言是「新型病毒急 / 慢內分泌效應」整合 framework，包括 fellow 考試經典 trap：dexamethasone-induced hyperglycemia、COVID-19 thyroiditis（subacute pattern）、ICU adrenal insufficiency、PASC autonomic + thyroid dysfunction、vaccine-induced thyroiditis。

全球 ~10 億 COVID-19 感染、~7 million 死亡（多 pulmonary + CV）；內分泌系統不免於 acute inflammatory response，特別 metabolic、adrenal、thyroid、pituitary、bone 軸；Long COVID（PASC）內分泌 sequelae 在 10-30% 感染者持續 ≥ 12 週。

與其他章 cross-ref： - Ch 11（Hypothyroidism + Thyroiditis） — Subacute thyroiditis pattern in COVID-19；vaccine-induced thyroiditis - Ch 13（Adrenal Cortex） — ICU AI；adrenal hemorrhage in severe COVID-19 - Ch 33-35（DM） — New-onset diabetes during COVID-19；dexamethasone-induced hyperglycemia - Ch 27（Mineral Metabolism） — Hypocalcemia 在 acute COVID-19 高 prevalence - Ch 6（Pituitary） — Pituitary involvement、apoplexy - Ch 17（Testes）+ Ch 25（Female Reproductive） — Sex hormones + reproductive effects - Ch 40（Obesity） — Obesity + COVID-19 嚴重度 paradox - Ch 38（DM Complications） — DKA + HHS during COVID-19 - Ch 44（Polyendocrine Autoimmune） — Vaccine-induced autoimmune thyroiditis；ICI-like phenomenon

2020-2025 關鍵更新（必背）： 1. RECOVERY trial 2020（NEJM）— Dexamethasone 6 mg/d × 10 d 顯著 ↓ severe COVID-19 mortality (~36% in ventilated)；改變 acute care 標準。 2. CoviDIAB Registry 2020-2024：發現 新發 DM during/after COVID-19 —— 部分 transient stress hyperglycemia + 部分 permanent T1D-like / T2D-like；SARS-CoV-2 對 β-cell 直接 ACE2-mediated effect 機轉假說。 3. Subacute COVID-19 Thyroiditis：類 viral subacute thyroiditis pattern；neck pain + transient hyperthyroid → hypothyroid → recovery；多在感染後 1-4 週發生。 4. Vaccine-induced thyroiditis（mRNA、特別 Pfizer + Moderna 2021-2024 reports）：subacute thyroiditis + Graves’ disease 部分 case；ICI-like immune-related endocrinopathy 警覺。 5. PASC (Post-Acute Sequelae of SARS-CoV-2) / Long COVID：症狀 ≥ 12 週後感染；~10-30% 感染者 受影響；內分泌 sequelae 包括：autonomic dysfunction（POTS）、thyroid dysfunction、adrenal “fatigue”-like、reproductive abnormalities。 6. Hypocalcemia in COVID-19 60-80% — 多 mild but 與 severity + mortality 相關；vit D deficiency 普遍。 7. Vertebral fractures 在 COVID-19 hospitalized 病人 ↑（多 pre-existing osteoporosis + steroid-induced）。 8. Apoplexy + pituitary involvement — rare but reported；ACE2 在 pituitary 表現；Sheehan-like presentation。 9. 2024 ENDO + ESE COVID-19 Endocrine Practice Statement — 整合 acute care + Long COVID surveillance。

本章在台灣專科考的重點分布：COVID-19 + DM 雙向關係 / Dexamethasone 6 mg/d RECOVERY → hyperglycemia 處置 / 新發 DM during COVID + CoviDIAB / Subacute thyroiditis pattern + 治療 / Hypocalcemia 60-80% prevalence / PASC POTS + thyroid dysfunction / Vaccine-induced thyroiditis（mRNA） / ICU adrenal insufficiency / Pituitary apoplexy in COVID-19。

47.1 🔥 1-Page Summary（15 核心重點，看完抓 70%）

15 點是「DM + 內分泌軸 + 疫苗 + Long COVID + 治療整合」維度乘下來的最少必備量。

47.1.1 Acute COVID-19 + DM（4 點）

COVID-19 + DM 雙向關係：
- DM 病人 COVID-19 嚴重度 / mortality ↑ 2-4×（特別 T2D + obesity + 高 HbA1c + DKA history）
- COVID-19 致 new-onset DM / 加速既有 DM 失控：
  - Stress hyperglycemia（acute illness）
  - Dexamethasone-induced hyperglycemia（治療後 days-weeks）
  - Direct β-cell SARS-CoV-2 effect via ACE2（CoviDIAB hypothesis）
  - 慢性發炎 + obesity worsening
- DKA + HHS in COVID-19：classic + severe；dexamethasone + 失控糖尿 + 脫水加成
- Treatment：individual；SGLT2i 在 DKA 風險警覺（部分 protocol 暫停 during acute COVID）；GLP1-RA + SGLT2i 不等於 contraindicated
Dexamethasone-induced hyperglycemia：
- RECOVERY trial 2020：dexamethasone 6 mg/d × 10 d → ↓ severe COVID-19 mortality (~36% in ventilated)
- 約 50-80% 接受 dexamethasone 的 hospitalized COVID-19 病人 develop hyperglycemia
- 機轉：cortisol-mediated insulin resistance + 胰島素 secretion impairment + 食慾變化
- Insulin sliding scale + basal-bolus 標準處置
- 出院後可能 persistent → 後 follow
CoviDIAB Registry + 新發 DM：
- 全球 registry 收集 COVID-19-associated 新發 DM cases
- 部分 transient stress hyperglycemia（resolve）
- 部分 permanent T1D-like / T2D-like（不可逆）
- 機轉假說：
  - SARS-CoV-2 + ACE2 receptor（β-cell 表現 ACE2）→ 直接感染 β-cell → islet inflammation → β-cell damage
  - Cytokine storm 加成 islet damage
  - 慢性 stress + obesity worsening
- 部分 case 表現為 fulminant T1D-like
- Surveillance：post-COVID 6 mo HbA1c + glucose
DM management during acute COVID-19：
- Glycemic target 個別化（多 140-180 mg/dL on dexamethasone）
- Avoid SGLT2i during acute if DKA risk（部分 protocol restart 後）
- Metformin 通常 stop during severe acute（lactic acidosis fear；部分 study reassuring）
- GLP1-RA continued if 已 stable
- DKA 標準處置：IV fluid + insulin drip + K replacement + mental status
- Continuous glucose monitoring（CGM） in ICU 部分 evidence

47.1.2 Obesity + Bone + Pituitary + Thyroid + Sex（4 點）

Obesity + COVID-19：
- Obesity（BMI ≥ 30）↑ COVID-19 嚴重度 ~46%、mortality ~48%
- 機轉：respiratory mechanics（diaphragm + lungs compressed）+ adipose tissue 慢性發炎 + ACE2 over-expression in adipose + immune dysfunction
- Vaccination response 也 obesity 病人 reduced（antibody titers 較低 + 短）
- Treatment：standard COVID protocols；prophylactic anticoagulation lower threshold；ICU admission threshold lower
Bone and Mineral Metabolism in COVID-19：
- Hypocalcemia 60-80% 在 hospitalized COVID-19；多 mild but 與 severity + mortality 相關
- 機轉：vit D deficiency + impaired Ca absorption + cytokine effect on PTH + Ca trafficking
- Vertebral fractures：hospitalized 病人 ↑ prevalence；多 pre-existing osteoporosis + steroid-induced（dexamethasone）
- Vitamin D deficiency 普遍 + 與 severity 相關（爭議 supplement 是否 protective）
- Treatment：correct hypocalcemia + Vit D supplementation + bone protection during prolonged steroid
Pituitary + Thyroid + Sex Hormones in COVID-19：
- Pituitary：rare apoplexy；ACE2 在 pituitary 表現；Sheehan-like presentation；hypopituitarism reports
- Thyroid：
  - Subacute thyroiditis（COVID-19 thyroiditis）：1-4 週後感染；neck pain + tender thyroid + transient hyperthyroid → hypothyroid → recovery；類 viral subacute thyroiditis pattern；NSAID + steroid 治療
  - Non-thyroidal illness syndrome（low T3） 在 ICU
  - Atypical Graves’ post-COVID reports
- Sex hormones：
  - Male hypogonadism 在 hospitalized COVID-19；severity 相關；多 transient
  - Menstrual irregularities post-COVID 報告；多 self-resolve
Vaccine-induced Endocrinopathy：
- Subacute thyroiditis 在 mRNA vaccine（Pfizer、Moderna）reports；多 days-weeks post-vaccine
- Graves’ disease 部分 case post-vaccine（特別在預先 autoantibody-positive 病人）
- Pituitary apoplexy rare reports
- ICI-like immune-related endocrinopathy 警覺
- Recommendation：vaccine-related endocrinopathy 不應 contraindication for booster；individual evaluation

47.1.3 Long COVID（PASC）+ 整合（3 點）

PASC（Post-Acute Sequelae of SARS-CoV-2）— Long COVID：
- WHO 定義：症狀 ≥ 12 週 after onset + 不能歸因 alternative diagnosis
- Prevalence：~10-30% 感染者 ≥ 12 週症狀；女性 + 中年 + 嚴重 acute infection 較高
- Symptoms 多系統：
  - Fatigue（最常見，60-80%）
  - Brain fog / cognitive impairment
  - Respiratory（dyspnea on exertion、reduced exercise tolerance）
  - Cardiac（POTS、palpitations、chest pain）
  - Autonomic dysfunction（POTS — postural orthostatic tachycardia syndrome）
  - Endocrine（thyroid dysfunction、reproductive abnormalities、adrenal “fatigue”-like）
  - Musculoskeletal（pain、weakness）
  - Mental health（anxiety、depression、insomnia）
- Pathophysiology hypotheses：
  - Persistent viral reservoir
  - Autoimmunity
  - Chronic inflammation
  - Microvascular damage / endothelial dysfunction
  - Mitochondrial dysfunction
  - Reactivation of latent viruses（EBV）
PASC Endocrine Sequelae：
- Thyroid dysfunction：persistent low T3、subclinical hypothyroid、Graves’-like；多 transient
- Reproductive abnormalities：men 持續 low testosterone；women menstrual irregularities + POI-like + miscarriage risk
- Adrenal “fatigue”-like：cortisol 多 normal range 但 symptoms persist；「functional adrenal insufficiency」概念
- Bone：persistent low BMD risk
- Insulin resistance + new-onset DM：CoviDIAB
- Treatment：對症 + lifestyle + 個別化 endocrine replacement if 確診 deficiency
PASC + POTS（Postural Orthostatic Tachycardia Syndrome）：
- PASC 中 ~20-30% 有 POTS
- 自律神經 dysfunction → 站立後 HR ↑ 30+ bpm + symptoms（dizzy、fatigue、palpitations）+ 無 OH
- 機轉：autoimmune + autonomic dysfunction + microvascular
- Treatment：
  - Lifestyle：高鹽 + 高水（2-3 L/day）+ compression stockings + 頭高斜睡 + 漸進性運動
  - Β-blocker low-dose（propranolol 10-20 mg PO bid）
  - Ivabradine 個別化
  - Midodrine 個別化
  - Fludrocortisone for refractory（小劑量）
  - Pyridostigmine in some cases

47.1.4 整合管理（2 點）

Acute COVID-19 endocrine baseline：
- 入院時 baseline：BG + HbA1c + Ca + 25(OH)D + TSH + cortisol（疑似 AI）
- Daily monitoring during steroid + ICU
- DKA / HHS 警覺 in DM 病人
- Hypocalcemia correct（critical illness Ca often falsely low）
Post-COVID surveillance（≥ 12 週後）：
- Thyroid panel（TSH + free T4 + thyroid antibody）
- Reproductive hormones（男 testosterone、女 menstrual + necessary FSH/LH/E2）
- Cortisol axis（morning cortisol + cosyntropin if symptoms）
- Glucose / HbA1c
- Bone density 個別化（特別 prolonged steroid）
- PASC clinics multi-disciplinary care

47.1.5 疫苗考量（1 點）

Vaccination strategy in endocrine patients：
- 沒有絕對 contraindication 對 endocrine disorders（包括 DM、AI、thyroid）
- AI 病人：sick day rules during illness；vaccination 不需 stress dose（個別化）
- Stable autoimmune thyroid 病人：vaccinate；個別化 follow-up TSH 6-12 wk post-vaccine
- Vaccine-induced endocrinopathy 罕見 + 個別化 management；不應 contraindicate booster

47.1.6 總體 framework（1 點）

「Acute / Chronic 雙軌 endocrine management」：
- Acute COVID-19：監測 + 急 management（DKA、AI、hypocalcemia、stress hyperglycemia）
- Long-term post-COVID：個別化 surveillance 12+ 週後；對症 + 替代 if deficiency；multidisciplinary PASC clinic

47.2 📌 必背數字（速覽，詳細在最後總表）

主題	數字
全球 COVID-19 感染 / 死亡	~10 億 / ~7 million
RECOVERY dexamethasone	6 mg/d × 10 d → ↓ severe COVID mortality 36%
DM 病人 COVID-19 mortality 增加	2-4×
Dexamethasone-induced hyperglycemia in hospitalized COVID	50-80%
Hypocalcemia in hospitalized COVID	60-80%
Subacute thyroiditis post-COVID timing	1-4 週
Obesity (BMI ≥ 30) + COVID 嚴重度 ↑ / mortality ↑	~46% / ~48%
PASC（Long COVID）prevalence	10-30%
PASC fatigue prevalence	60-80%
PASC + POTS prevalence	20-30%
ICU glycemic target on dex	140-180 mg/dL

47.3 📘 Detail（十個 deep sections，sub-section 對齊原書 ### 順序）

我們依原書 ### 順序對齊：① Introduction → ② DM → ③ Obesity → ④ Bone & Mineral → ⑤ Pituitary → ⑥ Thyroid → ⑦ Sex Hormones → ⑧ Vaccination → ⑨ PASC → ⑩ Summary。每個 axis 拆獨立 section 方便 fellow 對照原書段落。

47.3.1 Section 1 — Introduction and Overview of COVID-19 and Endocrine Disorders

47.3.1.1 1.1 Introduction and Overview

我們先把 SARS-CoV-2 為何影響內分泌系統的機制框架建好：

ACE2 為 SARS-CoV-2 主要受體
ACE2 在多 endocrine 組織高表現：胰 β-cell、thyroid、testes、ovaries、adrenal、pituitary、bone
直接組織損傷 + cytokine storm + microvascular damage + 治療相關（dexamethasone）+ 慢性發炎
COVID-19 內分泌效應分四軸：
1. Direct viral infection（SARS-CoV-2 進 endocrine cell via ACE2）
2. Cytokine + immune response（IL-6、TNFα、CRP）
3. Treatment-related（dexamethasone、remdesivir、tocilizumab）
4. Chronic post-acute sequelae（PASC / Long COVID）

47.3.2 Section 2 — COVID-19 and Diabetes Mellitus

47.3.2.1 2.1 Prevalence + Bidirectional Relationship

DM 病人 in COVID-19：~25-35% hospitalized COVID 病人有 DM
COVID-19 + DM 死亡率 2-4× 高於非 DM 病人

47.3.2.2 2.2 Increased Risk of Morbidity and Mortality in DM + COVID-19

機轉（為何 DM 病人 COVID-19 嚴重）： - Hyperglycemia 直接 impair immune response（neutrophil + macrophage function） - Microvascular dysfunction baseline → 加重 endothelial damage - Obesity 共存（多 T2D）→ respiratory mechanics 不利 - 慢性發炎 → cytokine storm 加成 - Endothelial ACE2 expression + COVID 致 endothelial dysfunction → vascular events - DKA + HHS 高 risk（dexamethasone + 失控糖尿 + 脫水加成）

Risk factors for severe COVID in DM： - HbA1c > 8% - T2D + obesity + 老年 + 男性 - Pre-existing CV / renal disease - Insulin user（multi-dose insulin 多 fragile） - DKA / HHS history

47.3.2.3 2.3 COVID-19 and New-Onset Diabetes

CoviDIAB Registry 全球數據： - 部分病人 transient stress hyperglycemia（resolve 後 weeks-months） - 部分病人 permanent DM-like：T1D-like / T2D-like / atypical - Children + adolescents 也報告

機轉假說：

SARS-CoV-2 + ACE2 (β-cell expression)
   → 直接感染 β-cell
   → islet inflammation
   → β-cell apoptosis / dysfunction
   → 急性 / 永久 insulin secretion 缺陷

加上：
   → Cytokine storm 加成 islet damage
   → Insulin resistance from steroid
   → 慢性 obesity + fasting + sedentary lifestyle worsen
   → 部分 case 表現為 fulminant T1D-like + DKA presentation

Surveillance：post-COVID 6 mo HbA1c + glucose；persistent → individual management

47.3.2.4 2.4 Treatment Considerations

During acute COVID： - Glycemic target：140-180 mg/dL（多 ICU on dex） - Insulin sliding scale + basal-bolus：standard - CGM in ICU 部分 evidence positive - Avoid SGLT2i during acute（DKA risk + dehydration risk） - Metformin 通常 stop in severe acute（lactic acidosis fear；scientific basis weak but cautious） - GLP1-RA continued if 已 stable + tolerating

DKA / HHS during COVID： - 同 standard DKA protocol：IV fluid + insulin drip + K replacement + mental status - Dexamethasone 加成：可能 DKA 即使非 type 1 病人；密切 monitoring

Post-discharge： - Glucose + HbA1c follow-up 1-3 mo - 部分 transient resolve；部分 persistent → 個別化 DM management

47.3.2.5 2.5 Dexamethasone-Induced Hyperglycemia（RECOVERY 2020）

RECOVERY trial 2020（NEJM）： - n=6,425 hospitalized COVID-19 - Dexamethasone 6 mg/day × 10 d（IV / oral）vs usual care - Mortality ↓： * Ventilated patients ↓ ~36% * Oxygen-only patients ↓ ~20% * Non-oxygen patients no benefit（甚至 harm trend） - 改變 acute COVID care 標準

Hyperglycemia incidence：50-80% hospitalized COVID + dexamethasone

機轉： - Cortisol-mediated insulin resistance（peripheral） - 胰島素 secretion impairment（β-cell stress） - Glucagon ↑ - 食慾變化 - Peak hyperglycemia mid-day to evening（dexamethasone half-life ~36 hr 但 metabolic effect 不平均）

Management： - Basal-bolus insulin 標準 - Adjustments from baseline：典型 30-50% increase on dexamethasone - Sliding scale supplementary - CGM if available - Discharge：dexamethasone 完成後 hyperglycemia 多 resolve；persistent → 後續 follow

47.3.3 Section 3 — Obesity and COVID-19

47.3.3.1 3.1 Risk increase by obesity（BMI ≥ 30）

BMI ≥ 30 → 嚴重 COVID 風險 ↑ ~46%、mortality ↑ ~48%（meta-analysis 2021）
BMI ≥ 35 effect 加倍
Younger obesity 病人 risk 顯著 increased（Williams stresses 「不要因為年輕就忽視」）

47.3.3.2 3.2 Mechanism of obesity → COVID severity

Respiratory mechanics：visceral fat 推 diaphragm → lung volume ↓ → ventilatory reserve ↓
ACE2 over-expression in adipose tissue → 病毒 entry sites 多
Adipose tissue 慢性發炎（cytokines、leptin、IL-6）→ cytokine storm 加成
Immune dysfunction：obesity 致 T cell exhaustion + reduced antibody response
Hyperinsulinemia（baseline）→ pro-inflammatory state
Microvascular dysfunction

47.3.3.3 3.3 Vaccination Response in Obesity

Obesity 病人 vaccine antibody titers ↓ + 短
Booster + higher vaccine dose 個別化考慮
Standard dose 仍 indicated（部分 protection 比無 vaccine 好）

47.3.3.4 3.4 Clinical Outcome + Treatment

Lower threshold for ICU admission
Prophylactic anticoagulation lower threshold（VTE risk 加成）
Standard COVID protocols + obesity-specific considerations
Supine position 對 obese 病人 oxygenation 不佳 → 多 prone positioning

47.3.4 Section 4 — Bone and Mineral Metabolism in COVID-19

47.3.4.1 4.1 Hypocalcemia — Prevalence + Severity

Hypocalcemia 60-80% hospitalized COVID-19
多 mild but 與 severity + mortality 相關
嚴重 hypocalcemia (Ca < 8 mg/dL) 更高 mortality

47.3.4.2 4.2 Hypocalcemia — 機轉與 corrected Ca 公式

Vitamin D deficiency baseline 普遍（特別 hospitalized + 老年）
Impaired Ca absorption（GI symptoms + decreased PO intake）
Cytokine effect on Ca trafficking
PTH dysregulation
Hungry bone-like phenomenon (rare)
Falsely low with hypoalbuminemia → always correct: corrected Ca = measured Ca + 0.8 × (4 − albumin)

47.3.4.3 4.3 Hypocalcemia — Treatment

IV Ca gluconate for symptomatic / severe (Ca < 7.5)
Oral Ca + Vit D for mild
Active vitamin D (calcitriol) for severe deficiency or renal failure

47.3.4.4 4.4 Vitamin D and COVID-19

Vit D 狀態 + COVID： - Vit D deficiency in COVID 病人 60-80% - Observational studies 顯示 deficient 病人 outcome 較差（因果性爭議） - RCT supplementation 結果 mixed： * COVID-19 mortality 部分 trial 改善 * Severity / recovery 不一致 * 2024 meta：marginal benefit；不應 routine high-dose - Recommendation：maintain adequate vit D（25(OH)D > 30 ng/mL）+ supplementation if deficient；不應 high-dose during acute COVID beyond physiologic replacement

47.3.4.5 4.5 Vertebral Fractures

Hospitalized COVID 病人 vertebral fracture prevalence ↑： - Pre-existing osteoporosis common - Steroid (dexamethasone) 加成 bone loss - Long bedrest 加成 - Older age

Treatment： - Bone density evaluation post-discharge if prolonged steroid - Bisphosphonate / denosumab 個別化（特別 prolonged steroid > 3 mo） - Vit D + Ca supplement - Early mobilization

47.3.5 Section 5 — The Pituitary and COVID-19

47.3.5.1 5.1 Apoplexy / hypopituitarism / ACE2 表現

Pituitary involvement rare but reported： - Pituitary apoplexy post-COVID（可能 related to hemodynamic instability + 凝血異常） - Hypopituitarism post-COVID 部分 case（hypothalamus / pituitary involvement） - ACE2 在 pituitary 表現（特別 anterior pituitary） - Sheehan-like presentation in severe COVID with hemodynamic compromise

評估： - 高度懷疑 → MRI + multi-axis hormonal panel - Replacement 個別化（HC + LT4 + sex steroids）

47.3.6 Section 6 — Thyroid and COVID-19

47.3.6.1 6.1 Subacute Thyroiditis (COVID-19 Thyroiditis)

經典 pattern： - 1-4 週後 COVID infection - Neck pain + tender thyroid + transient hyperthyroidism → hypothyroidism → recovery - 類 viral subacute thyroiditis（de Quervain’s-like） - 多 self-limited

Treatment： - NSAID for pain - Steroid if 嚴重 / 持續 - β-blocker for hyperthyroid symptoms（propranolol 10-20 mg PO bid） - Levothyroxine for hypothyroid phase（多 transient → 後可逐減）

47.3.6.2 6.2 Non-Thyroidal Illness Syndrome (NTI / Low T3 Syndrome)

Severe COVID 多 NTI pattern：low T3、normal/low T4、normal/low TSH
Don’t treat in absence of clear hypothyroid
多 acute illness recovery 後改善

47.3.6.3 6.3 Atypical Graves’ Post-COVID

部分 reports：post-COVID Graves’ onset
TRAb + thyroid uptake 確診
Standard Graves’ management（thionamide / RAI / surgery）

47.3.7 Section 7 — Sex Hormones and COVID-19

47.3.7.1 7.1 Male Hypogonadism

Hospitalized COVID 男性 testosterone 多 ↓（acute illness pattern）
Severity 相關
多 transient（recovery 後 rebound）
Persistent post-COVID hypogonadism：個別化 evaluation + replacement consideration

47.3.7.2 7.2 Female Reproductive

Menstrual irregularities post-COVID 報告
POI-like presentation rare
Pregnancy outcomes：preterm + low birth weight + miscarriage risk 部分 ↑
Vaccination during pregnancy：safe + 推薦（多國 guideline）

47.3.8 Section 8 — COVID-19 Vaccination and Endocrine Diseases

47.3.8.1 8.1 Vaccine-Induced Subacute Thyroiditis（mRNA）

mRNA vaccines (Pfizer + Moderna) reports；多 days-weeks post-vaccine
類 COVID-19-induced subacute thyroiditis
Self-limited；NSAID + 個別化 steroid

47.3.8.2 8.2 Vaccine-Induced Graves’ Disease

部分 reports post-vaccine（特別在預先 autoantibody-positive 病人）
Standard Graves’ management
不 contraindicate booster（individual evaluation）

47.3.8.3 8.3 Hashimoto Thyroiditis Flare

部分 reports；多 self-limited

47.3.8.4 8.4 Vaccine + Other Endocrine（pituitary apoplexy / adrenal / DM 反應）

Pituitary apoplexy rare reports
Adrenal events rare
DM 病人 vaccine response：reduced antibody titers in poor control；individualize booster

47.3.8.5 8.5 Vaccination Strategy in Endocrine Patients

沒有絕對 contraindication 對 endocrine disorders（包括 DM、AI、thyroid）： - AI 病人：vaccine 前 stress dose 不需（unless ill at time of vaccination）；sick day rules during fever / 不適 post-vaccine - Stable autoimmune thyroid 病人：vaccinate；TSH 6-12 wk post-vaccine 個別化 - Pregnant + breast feeding：mRNA vaccines safe + recommended - Vaccine-induced endocrinopathy 罕 + 個別化 management；不應 contraindicate booster

47.3.9 Section 9 — Post–Acute Sequelae of SARS-CoV-2（PASC / Long COVID）+ 整合 management

47.3.9.1 9.1 WHO 定義（PASC / Long COVID）

Post COVID-19 condition (Long COVID / PASC)： - 症狀 ≥ 12 週後 COVID-19 onset - 不能由 alternative diagnosis 解釋 - 多系統 + 變化 over time

47.3.9.2 9.2 Prevalence + Risk Factors（10–30%）

~10-30% 感染者 ≥ 12 週症狀
女性 > 男性（~1.5×）
中年 + 嚴重 acute infection 較高
Vaccination 部分 protective（vs unvaccinated）
Multiple infections + breakthrough infection 也 risk

47.3.9.3 9.3 Pathophysiology（persistent virus / autoimmunity / cytokine / mitochondrial）

Hypotheses： - Persistent viral reservoir（gut、CNS、vascular） - Autoimmunity（autoantibody emergence） - Chronic inflammation + cytokine dysregulation - Microvascular damage / endothelial dysfunction - Mitochondrial dysfunction - Reactivation of latent viruses（EBV、HHV-6） - Gut microbiome dysbiosis - Vagal nerve dysfunction

47.3.9.4 9.4 Symptomatology（多系統表）

多系統 + 變化：

系統	症狀
一般	Fatigue（最常見 60-80%）、low energy
神經	Brain fog、cognitive impairment、headache、dizziness、insomnia
呼吸	Dyspnea on exertion、reduced exercise tolerance、persistent cough
心血管	POTS、palpitations、chest pain、autonomic dysfunction
內分泌	Thyroid dysfunction、testosterone 低、menstrual irregularities、adrenal “fatigue”-like
肌骨	Pain、weakness、myalgia
心理	Anxiety、depression、PTSD-like
GI	腹痛、orthostasis、diarrhea
皮膚	Rash、persistent loss of taste / smell

47.3.9.5 9.5 Endocrine Determinants of PASC — Thyroid Dysfunction

Persistent low T3 / subclinical hypothyroid 多
Atypical Graves’ rare
TSH 多 normal but symptomatic improvement with treatment 在 selected case
Thyroid antibody screen in symptomatic
不建議 routine LT4 in NTI pattern with normal TSH

47.3.9.6 9.6 Endocrine Determinants of PASC — Adrenal “Fatigue”-Like

Cortisol 多 normal range but symptoms persist
「Functional adrenal insufficiency」 概念；機轉不清
Cosyntropin test 多 normal but inadequate cortisol secretion under stress
Hydrocortisone replacement individual（爭議）

47.3.9.7 9.7 Endocrine Determinants of PASC — Reproductive Abnormalities

Men：persistent low testosterone（部分 transient → 部分 permanent）
Women：menstrual irregularities + POI-like + miscarriage 風險增
Sexual dysfunction （男 ED + 女性慾下降）

47.3.9.8 9.8 Endocrine Determinants of PASC — Insulin Resistance + new-onset DM

CoviDIAB pattern
部分 transient + 部分 permanent
HbA1c 6 mo follow-up

47.3.9.9 9.9 Endocrine Determinants of PASC — Bone

Persistent low BMD risk（多 prolonged inactivity + steroid + chronic illness）
DEXA in high-risk

47.3.9.10 9.10 PASC + POTS（Postural Orthostatic Tachycardia Syndrome）

Definition： - 站立後 HR ↑ 30+ bpm（or HR > 120 bpm）within 10 min - + symptoms（dizzy、palpitations、fatigue、cognitive impairment） - 無 orthostatic hypotension - PASC 中 ~20-30%

Mechanism： - 自律神經 dysfunction - Microvascular damage - Autoimmune（一些 ganglionic acetylcholine receptor antibody 陽）

Diagnosis： - Tilt-table test - Active stand test（10 min stand） - Heart rate variability

Treatment： - Lifestyle： * 高鹽（10-12 g salt/day）+ 高水（2-3 L/day） * Compression stockings (waist-high preferred) * 頭高斜睡（HOB elevated 4-6 inches） * 漸進性運動 + recumbent exercise（rowing、recumbent bike → 後 standing） * 避立即站起 + 坐到躺先慢 - Medications： * β-blocker low-dose (propranolol 10-20 mg PO bid 或 metoprolol 12.5-25 mg) — 注意 asthma + bradycardia * Ivabradine 2.5-7.5 mg PO bid — funny channel inhibitor（不 cause hypotension；好選擇） * Midodrine 5-10 mg PO tid — α-1 agonist（vasoconstriction） * Fludrocortisone 0.05-0.2 mg/d — for refractory（hyper-volume） * Pyridostigmine 30-60 mg PO tid — autonomic in some - Multidisciplinary PASC clinic

47.3.9.11 9.11 PASC Management Integration（6-step pathway）

Step 1: 完整 history + symptom-system map + onset post-COVID confirm
Step 2: Baseline endocrine: TSH+free T4+thyroid Ab, testosterone (男), 
        menstrual + FSH/LH/E2 (女), morning cortisol, glucose+HbA1c, 25(OH)D
Step 3: Other workup:
   □ Cardiology: ECG, echo if symptoms; tilt-table for POTS
   □ Pulmonary: PFT, 6-min walk
   □ Neurology: neurocognitive testing
   □ Mental health: depression + anxiety + PTSD screen
Step 4: Symptom-targeted treatment:
   □ Fatigue: graded exercise (controversial; PEM caution) + sleep hygiene + 個別化
   □ POTS: lifestyle + β-blocker / ivabradine / midodrine
   □ Brain fog: cognitive rehab + adequate sleep + 個別化
   □ Endocrine: 個別化 replacement if confirmed deficiency (不 routine LT4 for normal TSH)
   □ Mental health: CBT + 必要時藥物
Step 5: Multidisciplinary PASC clinic + follow-up q 3-6 mo
Step 6: Vaccination: continue boosters per guideline

47.3.9.12 9.12 整合管理 + Future（multidisciplinary clinic / 兒童 PASC / treatment trials）

PASC clinic 多學科：infectious disease + cardiology + endocrinology + 心理 + 復健
Research focus：persistent virus + autoimmunity + microbiome + autonomic
Treatment trials：metformin (COVID-OUT)、low-dose naltrexone、antihistamine、anti-fibrotic
Vaccination strategy：boosters individual；mRNA + 異質 strategy
Pediatric PASC：lower prevalence but real；school + functional rehab focus

47.3.10 Section 10 — Summary（章末整合）

對齊原書 ### Summary 段落，把全章四軸 framework 收尾再強化一次。Fellow 看完整章後，這段就是「上場前最後一張紙」。

四軸 framework 一頁回顧：

Direct viral effect via ACE2 — β-cell、thyroid、testes、ovaries、adrenal、pituitary、bone 都有 ACE2 表現，SARS-CoV-2 可直接侵犯，造成新發 DM（CoviDIAB）、subacute thyroiditis、orchitis、apoplexy。
Cytokine + immune response — IL-6、TNFα、CRP 為主的 cytokine storm 加成 hypocalcemia、NTI、adrenal stress、insulin resistance；同時 microvascular damage 加重 endothelial dysfunction。
Treatment-related — RECOVERY 2020 確立 dexamethasone 6 mg/d × 10 d 在 ventilated 病人 ↓ mortality 36%（oxygen-only ↓ ~20%、non-oxygen 無 benefit），代價是 hyperglycemia 50–80% + DKA risk + bone loss + muscle wasting + 重症 AI risk；急性期應 avoid SGLT2i、metformin caution、insulin basal-bolus 拉高 30–50%。
Chronic post-acute sequelae（PASC / Long COVID） — ~10–30% 感染者 ≥ 12 週多系統症狀，內分泌軸包括 thyroid dysfunction、adrenal「fatigue」-like、男性 testosterone 持續低、女性月經不規則 + POI-like、insulin resistance + new-onset DM、bone loss；POTS 出現於 PASC ~20–30%，治療層級為 lifestyle（高鹽 10–12 g/d、compression stocking、recumbent exercise）→ ivabradine 2.5–7.5 mg bid → β-blocker / midodrine 5–10 mg tid → fludrocortisone 0.05–0.2 mg/d → pyridostigmine。

實戰要點（fellow 上場 5 條）：

Hypocalcemia 60–80% 是 acute COVID 病房最常被忽略的 lab，corrected Ca = measured Ca + 0.8 ×（4 − albumin）一定要算；symptomatic / Ca < 7.5 上 IV Ca gluconate。
Subacute thyroiditis 1–4 週 post-COVID，neck pain + transient hyperthyroid → hypothyroid → recovery，治療 NSAID + β-blocker（propranolol 10–20 mg PO bid）+ 嚴重時 steroid；疫苗（mRNA）後也可發生，pattern 相同。
Pituitary apoplexy rare 但 severe COVID + hemodynamic instability + 凝血異常情境要警覺；MRI + 多軸 hormonal panel + HC + LT4 個別化。
PASC 不要 routine LT4 for normal TSH；PEM（post-exertional malaise）警覺，避免一味 graded exercise therapy（GET）。
疫苗策略：endocrine disorder（DM、AI、thyroid）皆無絕對 contraindication；AI 病人 vaccine 前不需 stress dose，sick day rules during fever / 不適 post-vaccine；vaccine-induced endocrinopathy 不應 contraindicate booster。

台灣特化（疾管署 / 健保）：

疾管署 2024 維持「住院 + 重症 confirmed COVID + 高風險族群」為公費抗病毒藥（Paxlovid / Molnupiravir）目標，DM、obesity、慢性內分泌疾病皆列高風險；老年 + DM + HbA1c 控制不佳者建議盡早通報、5 日內啟用。
健保 ART era 後續：dexamethasone（6 mg/d × 10 d）+ remdesivir + tocilizumab 為住院主軸；CGM 在 ICU + 重症 DM 個別化（自費為主）；ivabradine 在 POTS 屬適應症外用法（off-label），需個別申請。
PASC 多由家醫科 / 感染科 / 復健科聯合門診，內分泌端建議 baseline TSH + free T4 + thyroid Ab + morning cortisol + testosterone（男）+ FSH/LH/E2（女）+ HbA1c + 25(OH)D + DEXA（高風險），symptom-targeted treatment + q3–6 mo follow。

指引年份對齊：RECOVERY 2020（NEJM）/ CoviDIAB 2020–2024 / WHO Post COVID-19 Condition 2024 update / NICE Long COVID guideline 2024 / 2024 ENDO + ESE COVID-19 Endocrine Practice Statement / 疾管署 COVID-19 公費抗病毒藥申請流程 2024。

47.4 🎯 Self-test 25 MCQ

範圍涵蓋 6 sections，臨床情境為主；每題完整詳解。

47.4.1 Q1（RECOVERY trial）

RECOVERY trial 2020 主要結果？

A. Dexamethasone 對所有 COVID-19 病人有效
B. Dexamethasone 6 mg/d × 10 d → 通氣病人 mortality ↓ 36%；oxygen-only ↓ 20%；non-oxygen 無 benefit
C. Hydroxychloroquine 改善 outcome
D. Remdesivir 改變 mortality
E. Dexamethasone 對 mild COVID 也有效

答案：B

RECOVERY 2020 (NEJM, n=6,425)：dexamethasone 6 mg/d × 10 d 對需要 oxygen / ventilation 病人 ↓ mortality；non-oxygen 病人 no benefit (甚至 harm trend)。改變 acute COVID 標準。Hyperglycemia 50-80% in dex-treated patients。

47.4.2 Q2（DM + COVID 機轉）

COVID-19 致 new-onset DM 主要機轉假說？

A. ART 直接致 DM
B. SARS-CoV-2 進 β-cell via ACE2 + cytokine storm + steroid + chronic stress
C. 完全 sterile
D. 純基因
E. Viral genome integration

答案：B

CoviDIAB Registry hypothesis：β-cell ACE2 expression + 病毒直接感染 + cytokine storm + dexamethasone-induced + chronic stress + obesity worsening。部分 transient stress hyperglycemia + 部分 permanent T1D-like / T2D-like。Surveillance：post-COVID 6 mo HbA1c。

47.4.3 Q3（Dexamethasone hyperglycemia）

55 歲 T2D HbA1c 7.5% + acute COVID-19 接受 dexamethasone 6 mg/d。下列最合適 glycemic management？

A. 不變 baseline therapy
B. Basal-bolus insulin + sliding scale；增加 baseline dose 30-50%；target 140-180；CGM if available
C. SGLT2i first-line
D. Stop all DM medication
E. PRRT

答案：B

Dex-induced hyperglycemia 50-80% in hospitalized COVID；機轉 cortisol-mediated IR + 胰島素 secretion impairment。Basal-bolus insulin 標準；Adjustments 30-50% from baseline；target 140-180 (ICU)；CGM 部分 evidence；avoid SGLT2i (DKA risk in acute)；metformin 通常 stop in severe acute (lactic acidosis fear；部分 study reassuring)；GLP1-RA continued if stable。

47.4.4 Q4（DKA + COVID + dexamethasone）

30 歲 T1D + acute COVID-19 + dexamethasone 6 mg/d × 5 d → DKA presenting：BG 450 + ketones + pH 7.20。下列最合適？

A. Metformin only
B. Standard DKA protocol：IV fluid + insulin drip + K replacement + mental status；continue dexamethasone (RECOVERY indication) + adjust insulin
C. Stop all medications
D. SGLT2i
E. Dialysis first-line

答案：B

DKA in COVID + dexamethasone：standard DKA protocol 同 non-COVID。Dexamethasone 因 RECOVERY indication 通常 continue (mortality benefit > DKA risk balanced)；adjust insulin drip 補償。Avoid SGLT2i in acute DKA。HHS 部分 case 加成 (severe dehydration)。

47.4.5 Q5（COVID-19 thyroiditis）

35 歲女性 acute COVID-19 後 2 週出現 neck pain + tender thyroid + tachycardia + 體重下降。TSH < 0.01 + free T4 elevated + ESR ↑。下列最可能？

A. Graves’
B. COVID-19-related subacute thyroiditis（類 viral subacute thyroiditis）
C. Toxic adenoma
D. Hashimoto with hyperphase
E. Painless thyroiditis

答案：B

COVID-19-induced subacute thyroiditis 1-4 週 post-infection；neck pain + tender + transient hyperthyroid → hypothyroid → recovery；類 de Quervain’s-like。Treatment：NSAID + 個別化 steroid + β-blocker for hyperthyroid symptoms（propranolol）+ levothyroxine for hypothyroid phase（多 transient）。

47.4.6 Q6（Hypocalcemia in COVID）

COVID-19 hospitalized 病人 hypocalcemia prevalence + 主要機轉？

A. < 10% prevalence
B. 60-80% prevalence；vit D deficiency + impaired Ca absorption + cytokine + albumin correction
C. 100% prevalence
D. 純 albumin artifact
E. 純 dexamethasone effect

答案：B

Hypocalcemia 60-80% in hospitalized COVID；多 mild but 與 severity + mortality 相關。Mechanisms：Vit D deficiency + GI Ca absorption impaired + cytokine + PTH dysregulation + falsely low with hypoalbuminemia (always correct: corrected Ca = measured + 0.8 × (4 − albumin))。

47.4.7 Q7（PASC definition）

WHO PASC (Long COVID) 定義？

A. ≥ 4 週 symptoms
B. ≥ 12 週 after onset + 不能 alternative diagnosis 解釋
C. ≥ 24 週
D. 必伴 fatigue
E. 必伴 brain fog

答案：B

WHO Post COVID-19 condition：症狀 ≥ 12 週 after onset + 不能由 alternative diagnosis 解釋；多系統 + 變化 over time。Prevalence ~10-30% 感染者。Risk factors：女性 + 中年 + severe acute + multiple infections + unvaccinated。

47.4.8 Q8（POTS in PASC）

PASC + 站立後 HR ↑ 35 bpm + 無 OH + 持續 fatigue + brain fog。下列最可能？

A. Vasovagal
B. Anxiety only
C. POTS（postural orthostatic tachycardia syndrome）
D. Pheochromocytoma
E. Dysrhythmia

答案：C

POTS：站立後 HR ↑ 30+ bpm (or HR > 120) within 10 min + symptoms (dizzy、palpitations、fatigue、cognitive impairment) + 無 OH。PASC 中 ~20-30%。Mechanism：自律神經 dysfunction + microvascular + autoimmune (acetylcholine receptor antibodies)。Diagnosis：tilt-table or active stand test。

47.4.9 Q9（POTS treatment）

PASC + POTS 30 歲女性 first-line treatment？

A. Heart transplant
B. Lifestyle (高鹽 10-12 g + 高水 2-3 L + compression stockings + 漸進性 recumbent → standing 運動) + β-blocker low-dose 或 ivabradine
C. ACE inhibitor
D. SGLT2i
E. Tirzepatide

答案：B

POTS Treatment：Lifestyle first（高鹽 + 高水 + compression + recumbent exercise）+ medications（β-blocker propranolol 10-20 mg bid + ivabradine 2.5-7.5 mg bid 不致 hypotension + midodrine + fludrocortisone for refractory + pyridostigmine in some）。Recumbent → standing 漸進性運動 重要（PEM 警覺）。Multidisciplinary PASC clinic。

47.4.10 Q10（Obesity + COVID severity）

BMI ≥ 30 在 COVID-19 mortality 增加比率？

A. 不變
B. ~20%
C. ~48%
D. 100%
E. < 10%

答案：C

Meta-analysis 2021：BMI ≥ 30 → severe COVID risk ↑ ~46%、mortality ↑ ~48%。Mechanism：respiratory mechanics (visceral fat → lung volume ↓) + ACE2 over-expression in adipose + chronic inflammation + immune dysfunction + microvascular。Vaccination response ↓ in obesity。

47.4.11 Q11（Vaccine-induced thyroiditis）

30 歲女性 COVID-19 mRNA vaccine (Pfizer) 14 d 後出現 neck pain + transient hyperthyroid + 後 hypothyroid。下列最可能？

A. Vaccine 致永久 hypothyroid
B. mRNA Vaccine-induced subacute thyroiditis（類 COVID-19-induced subacute thyroiditis）
C. Iodine reaction
D. Autoimmune
E. Coincidence only

答案：B

mRNA vaccines (Pfizer + Moderna) 報告 subacute thyroiditis；多 days-weeks post-vaccine；類 COVID-19-induced thyroiditis pattern；self-limited。Treatment：NSAID + steroid + β-blocker individual。不 contraindicate booster；individual evaluation。

47.4.12 Q12（Pituitary apoplexy in COVID）

50 歲男 acute severe COVID-19 + 突發 severe headache + 視野缺損 + low cortisol。下列最緊急 management？

A. 觀察
B. Stress dose hydrocortisone IV + MRI + 緊急 hormone panel + 必要 surgical decompression
C. Antiviral only
D. Anticoagulation only
E. Steroid forever

答案：B

Pituitary apoplexy in COVID-19 rare but reported；hemodynamic instability + 凝血異常致；ACE2 在 pituitary 表現可能 contribute。Stress dose hydrocortisone (100 mg IV bolus + 50 mg q 6 h) + MRI + multi-axis hormone panel + 必要 surgical decompression for visual loss / 持續壓迫。Long-term hormone replacement individual。

47.4.13 Q13（Vit D in COVID）

Vit D supplementation in COVID-19？

A. High-dose 預防 COVID
B. Maintain adequate vit D (25(OH)D > 30 ng/mL)；deficient 時補；不應 high-dose during acute beyond physiologic
C. 100,000 IU q d 治癒
D. Active calcitriol routine
E. 不需 replace

答案：B

Vit D 與 COVID-19 mortality observational positive associations + RCT supplementation 結果 mixed (2024 meta marginal benefit)。Maintain adequate vit D (1000-2000 IU/d 標準)；deficient (< 20-30 ng/mL) 時 higher dose loading then maintenance；不 routine high-dose during acute COVID beyond physiologic replacement。

47.4.14 Q14（New-onset DM post-COVID）

35 歲 BMI 24 + 無 DM history + post-COVID 1 mo 出現 polyuria + polydipsia + BG 320 + ketones positive + GAD Ab negative。下列最可能？

A. T1D + COVID coincidence
B. CoviDIAB-pattern fulminant DM (T1D-like)
C. T2D from obesity
D. MODY
E. Drug-induced

答案：B

CoviDIAB 報告 fulminant T1D-like presentations post-COVID；機轉 SARS-CoV-2 + ACE2 (β-cell) + cytokine + steroid contribution。GAD Ab negative + acute presentation 仍可能 covid-induced；標準 DKA management + insulin replacement + 後 endocrinology follow-up。Surveillance：Post-COVID 6 mo HbA1c + glucose 對所有 high-risk。

47.4.15 Q15（Avoid SGLT2i in acute COVID）

COVID-19 + DM 病人 acute critical illness。下列 DM 藥物最警示 avoid？

A. Insulin
B. Metformin
C. SGLT2i (DKA + dehydration risk in acute illness)
D. GLP1-RA stable
E. DPP4i

答案：C

SGLT2i + acute illness → DKA risk + dehydration risk increased；** acute COVID 多 protocol 暫停 SGLT2i**；可 restart 後 stable。Metformin 通常 stop in severe acute (lactic acidosis fear; basis weak but cautious)；GLP1-RA continued if stable。Insulin sliding scale + basal-bolus 標準。

47.4.16 Q16（Adrenal “fatigue”-like in PASC）

30 歲女 PASC 6 mo + 持續 fatigue + cortisol 8 am normal + cosyntropin response normal。下列最合適？

A. Lifelong HC
B. 不 routine HC replacement；focus on lifestyle + sleep + 多軸 PASC management
C. Pasireotide
D. 心理諮商 only
E. Mineralocorticoid

答案：B

PASC adrenal “fatigue”-like：cortisol 多 normal range + cosyntropin normal but symptoms persist；「functional adrenal insufficiency」概念有爭議。不 routine HC replacement in normal cortisol；focus on lifestyle + sleep + 多軸 PASC management；HC replacement 個別化 (controversial)。

47.4.17 Q17（COVID-19 + DKA + HHS）

35 歲 T2D + acute COVID-19 + dexamethasone 6 mg/d × 4 d → mental status changes + BG 600 + Na 158 + osmolality 350。下列最可能？

A. Pure DKA
B. Mixed DKA + HHS (hyperosmolar)；dexamethasone 加成 hyperglycemia + dehydration + 失控糖尿
C. SIADH
D. Adrenal crisis
E. Lactic acidosis

答案：B

Mixed DKA + HHS in dex-treated COVID 警示；dehydration + 失控糖尿 + dexamethasone 加成；mental status 多嚴重。Treatment：IV fluid + insulin drip + K + 緩慢 osmolality correction (avoid cerebral edema)；CGM 助管理。

47.4.18 Q18（Vaccination + AI）

75 歲 Addison’s disease 病人 COVID-19 booster vaccination。下列最合適？

A. 必須 stress dose pre-vaccination
B. 個別化；通常不需 stress dose pre-vaccination；sick day rules during fever / 不適 post-vaccine
C. Contraindicate vaccine
D. 必住院 vaccinate
E. 換 fludrocortisone only

答案：B

AI 病人 vaccination：沒有 absolute contraindication；通常不需 stress dose pre-vaccination；sick day rules during fever / 不適 post-vaccine (double dose for 24-48 hr if 不適)；continue routine HC + Fludrocortisone。Multidisciplinary care。

47.4.19 Q19（PASC PEM）

PASC 30 歲女 + 嚴重 fatigue + 運動 24-48 hr 後 worsening。下列最重要 caution？

A. 立即 high-intensity exercise
B. Post-exertional malaise (PEM) — 漸進性 recumbent → standing exercise；avoid graded exercise therapy (GET) too aggressive；PASC PEM 類 ME/CFS
C. Bed rest forever
D. Cardiac transplant
E. 必不能運動

答案：B

PASC + PEM = post-exertional malaise (24-72 hr 後運動 worsening)；類 ME/CFS pattern。避免 aggressive graded exercise therapy (GET)；改用 pacing + recumbent → standing 漸進性 + recumbent exercise (rowing, recumbent bike) → 後 standing；emphasis on activity tolerance 不超 (heart rate-based pacing)。

47.4.20 Q20（Pediatric PASC）

8 歲兒童 post-COVID 8 mo + persistent fatigue + 學業困難 + 心理症狀。下列最現代 paradigm？

A. 兒童不會 PASC
B. PASC in children real but lower prevalence；focus on school accommodation + functional rehab + 心理支持 + multidisciplinary clinic
C. 純心理
D. 立即住院
E. 純藥物

答案：B

Pediatric PASC：lower prevalence than adult but real；symptom 類 (fatigue + cognitive + functional decline)；school accommodations + graded return to activities + functional rehab + 心理支持 + multidisciplinary care 重要。Vaccination 推薦。

47.4.21 Q21（綜合 — DKA + COVID + 內分泌 baseline）

新發 DKA in 50 歲 + COVID-19 hospitalization + dexamethasone 6 mg/d。下列最 comprehensive endocrine baseline + ongoing？

A. 只 BG
B. BG + HbA1c + ketones + electrolytes + ABG + serum osmolality + lactate + Ca + Mg + P + 25(OH)D + cortisol (baseline + cosyntropin if symptomatic AI) + TSH + free T4 + albumin (Ca correction) + lipid + LFT + creatinine
C. 只 ABG
D. 心電圖 only
E. 不需 baseline

答案：B

Acute COVID + 內分泌 critical illness baseline 全面；後 PASC surveillance + 個別化 follow-up。Multidisciplinary intensive care + endocrinology + critical care + multidisciplinary management。

47.4.22 Q22（PASC + thyroid）

PASC 25 歲女 + 持續 fatigue + cold intolerance + TSH 4.5 (normal range slightly high) + free T4 normal + thyroid Ab negative。下列最合適？

A. 立即 LT4 高劑量
B. 不 routine LT4；continued surveillance；個別化 trial of LT4 only if symptomatic + 6 wk re-evaluate；多軸 PASC management
C. Total thyroidectomy
D. Methimazole
E. RAI

答案：B

PASC + subclinical thyroid changes (TSH slightly elevated + free T4 normal)：不 routine LT4 in normal range；個別化 trial 6 wk evaluation；多軸 PASC management 重要。NTI pattern (low T3 normal TSH/T4) 多 acute illness recovery 後改善。

47.4.23 Q23（綜合 — Long COVID 多軸）

35 歲女 PASC 6 mo + fatigue + brain fog + POTS + 月經紊亂 + low-normal cortisol。下列最 comprehensive plan？

A. 單一藥物
B. Multidisciplinary PASC clinic：lifestyle + symptom-targeted (POTS lifestyle + β-blocker / ivabradine + midodrine) + endocrine surveillance (TSH + cortisol + reproductive hormones) + 心理 + cognitive rehab + graded recumbent → standing exercise + 月經 evaluation
C. Stop all medications
D. 立即 thyroid surgery
E. 純藥物 only

答案：B

PASC 多軸 management 必 multidisciplinary：內分泌 + 心血管 + 神經 + 心理 + 復健；symptom-targeted treatment for POTS + brain fog + thyroid + 月經 + 心理；vaccination boosters + 預防 reinfection。Research：metformin (COVID-OUT) + low-dose naltrexone + antihistamine 試驗中。

47.4.24 Q24（Vaccine response + DM）

DM 病人 HbA1c 9.5% COVID-19 vaccine response？

A. 完全 normal
B. Reduced antibody response in poor glycemic control (HbA1c > 8-9%)；個別化 booster 強化；emphasize vaccination 仍 indicated
C. Vaccine 無效
D. 必雙劑
E. Vaccine contraindicated

答案：B

Poor glycemic control DM 病人 vaccine antibody response 可能 reduced；emphasize vaccination 仍 indicated (some protection > none)；個別化 booster + 改善 glycemic control 同時。Obesity + immunosuppression 同樣 reduced response。

47.4.25 Q25（綜合應用 — multi-axis COVID + endocrine）

70 歲男 T2D + obesity + ART (HIV) + acute COVID-19 hospitalized + dexamethasone 6 mg/d × 5 d → BG 380 + Ca 7.2 + cortisol 6 (low) + neck pain + tender thyroid + TSH < 0.1 (3 wk post-acute)。下列最現代整合？

A. 單軸 management
B. Multidisciplinary acute + post-acute care：dex glycemic control (basal-bolus) + Ca correction (IV gluconate + Vit D supplement) + cosyntropin test + stress dose HC if AI + COVID-19 thyroiditis (NSAID + β-blocker + 個別化 steroid + LT4 if subsequent hypothyroid) + ART switch consideration if drug interaction + post-discharge HbA1c 6 mo (CoviDIAB) + thyroid follow-up + 多學科 PASC clinic
C. 只 antibiotic
D. 純 supportive
E. Single hormone replacement

答案：B

Multi-axis COVID + endocrine 整合 management： 1. Acute glycemic control on dex (basal-bolus + sliding scale) 2. Hypocalcemia correction (IV Ca + Vit D) 3. Cortisol axis evaluation (cosyntropin) + stress dose HC if AI 4. COVID-19 thyroiditis: NSAID + 個別化 steroid + β-blocker + LT4 individual 5. ART drug interaction consideration (Ch 46 cross-ref) 6. Post-discharge: HbA1c 6 mo (CoviDIAB) + thyroid follow-up 7. Multidisciplinary PASC clinic post-hospitalization 8. 「Multi-system COVID + multi-endocrine + multi-disciplinary」典型現代 paradigm

47.5 🎯 隨堂 7 Cases

#	患者	診斷	重點 take-home
1	55 歲 T2D HbA1c 7.5% + acute COVID + dex 6 mg	Dexamethasone hyperglycemia in COVID	Basal-bolus + 30-50% increase + target 140-180 + post-discharge follow-up
2	35 歲女 acute COVID 後 2 週 neck pain + transient hyperthyroid	COVID-19 subacute thyroiditis	NSAID + 個別化 steroid + β-blocker + LT4 transient phase
3	30 歲女 BMI 24 + post-COVID 1 mo + DKA + GAD Ab negative	CoviDIAB fulminant T1D-like	標準 DKA + insulin replacement + ACE2 + β-cell hypothesis + 6 mo HbA1c follow
4	25 歲女 Pfizer mRNA 14 d 後 neck pain + thyroiditis	Vaccine-induced subacute thyroiditis	NSAID + 個別化 steroid + 不 contraindicate booster
5	30 歲女 PASC 6 mo + 持續 fatigue + brain fog + 站立後 HR ↑ 35	PASC + POTS	高鹽 + 高水 + compression + recumbent exercise + β-blocker / ivabradine + multidisciplinary
6	50 歲男 severe COVID + 突發頭痛 + 視野缺損 + low cortisol	Pituitary apoplexy in COVID	Stress dose HC + MRI + multi-axis hormone + 必要 surgical decompression
7	70 歲男 multi-comorbidity + acute COVID + dex + 多軸 endocrine 異常	Multi-system COVID + endocrine	Multidisciplinary acute + PASC clinic 整合

47.6 🌟 8 Pearls

RECOVERY trial 2020 改變 acute COVID care：Dexamethasone 6 mg/d × 10 d → 通氣病人 mortality ↓ 36%；hyperglycemia 50-80%（必 anticipate + manage）。
CoviDIAB hypothesis：SARS-CoV-2 + ACE2 在 β-cell → 直接感染 + cytokine + steroid + chronic stress；post-COVID 6 mo HbA1c surveillance 對所有 high-risk。
Hypocalcemia in COVID 60-80%：always correct for albumin (corrected Ca = measured + 0.8 × (4 − albumin))；嚴重 → IV Ca gluconate；Vit D + Ca supplement。
COVID-19 thyroiditis 1-4 週 post-infection：類 viral subacute pattern；transient hyperthyroid → hypothyroid → recovery；NSAID + β-blocker + 個別化 steroid + transient LT4。
PASC ~10-30% 感染者 ≥ 12 週；多系統；女性 + 中年較高；vaccination 部分 protective；multi-axis multidisciplinary management 必要。
PASC + POTS ~20-30%：站立後 HR ↑ 30+ bpm + symptoms；lifestyle (高鹽 + 高水 + compression + recumbent exercise) + β-blocker / ivabradine + midodrine + fludrocortisone；避免 aggressive graded exercise therapy (PEM 警覺)。
mRNA Vaccine-induced thyroiditis rare but real；不 contraindicate booster；individual evaluation；vaccine-induced endocrinopathy 與 ICI 類比 thinking 有用。
Avoid SGLT2i in acute COVID + dexamethasone：DKA + dehydration risk；restart 後 stable；metformin 通常 stop in severe acute（基於 cautious）；GLP1-RA continued if stable。

47.7 🔗 Cross-ref to Other Chapters

連到的章節	對位的內容
Ch 11（Hypothyroidism + Thyroiditis）	Subacute thyroiditis pattern + NTI
Ch 13（Adrenal Cortex）	ICU AI + adrenal hemorrhage in severe COVID
Ch 33-35（DM）	New-onset DM + dex hyperglycemia + DKA
Ch 27（Mineral Metabolism）	Hypocalcemia in acute COVID
Ch 6（Pituitary）	Pituitary apoplexy + ACE2 expression
Ch 17 + 25（Reproductive）	Sex hormones + menstrual irregularities
Ch 40（Obesity）	Obesity + COVID severity paradox
Ch 38（Complications）	DKA + HHS during COVID
Ch 44（Polyendocrine Autoimmune）	Vaccine-induced autoimmune endocrinopathy
Ch 46（HIV/AIDS）	Co-infection + drug interaction considerations

47.8 📌 必背數字總表（章末整理 ~50 條）

47.8.1 流行

主題	數字
全球 COVID-19 感染	~10 億
全球 COVID-19 死亡	~7 million
DM 病人 COVID 死亡率增加	2-4×
BMI ≥ 30 + COVID 嚴重度 ↑	~46%
BMI ≥ 30 + COVID 死亡率 ↑	~48%
Hospitalized COVID + DM prevalence	25-35%
Hypocalcemia in hospitalized COVID	60-80%
Vit D deficiency in hospitalized COVID	60-80%
Dexamethasone-induced hyperglycemia in COVID	50-80%
PASC prevalence	10-30%
PASC + POTS	20-30%
PASC fatigue	60-80%
Subacute thyroiditis post-COVID timing	1-4 週

47.8.2 Treatment

主題	數字
RECOVERY dexamethasone	6 mg/d × 10 d
RECOVERY mortality 改善 (ventilated)	~36%
RECOVERY mortality 改善 (oxygen-only)	~20%
RECOVERY non-oxygen	No benefit
Acute COVID glycemic target	140-180 mg/dL
Insulin baseline 增量 on dex	30-50%
Vit D maintenance	1000-2000 IU/d
25(OH)D target	> 30 ng/mL
Corrected Ca formula	measured + 0.8 × (4 − albumin)

47.8.3 POTS Management

治療	劑量
高鹽	10-12 g/day
高水	2-3 L/day
Propranolol	10-20 mg PO bid
Ivabradine	2.5-7.5 mg PO bid
Midodrine	5-10 mg PO tid
Fludrocortisone	0.05-0.2 mg/d (refractory)
Pyridostigmine	30-60 mg PO tid

47.8.4 COVID Thyroiditis

主題	數字
Onset post-infection	1-4 週
NSAID for pain	First-line
Steroid for severe	個別化
LT4 for hypo phase	Transient
β-blocker (propranolol)	10-20 mg bid

47.8.5 Vaccine-induced

主題	內容
mRNA vaccines (Pfizer + Moderna)	主要 reports
Subacute thyroiditis	days-weeks post-vaccine
Graves’	部分 case
Pituitary apoplexy	rare
Booster contraindication	不應 contraindicate

47.8.6 Trials / 年份

Trial	年	結論
RECOVERY	2020	Dexamethasone severe COVID mortality ↓
CoviDIAB Registry	2020-2024	New-onset DM during/after COVID
2024 ENDO + ESE	2024	COVID-19 endocrine practice statement
COVID-OUT (metformin trial)	進行中	Long COVID prevention investigation

47.9 📖 章末小結

Williams 15e Ch 47 把 COVID-19 對內分泌系統的 acute / chronic / vaccine 影響整合在「四軸 framework」下。我們用五句話收尾：

「Acute / Chronic 雙軌」：Acute COVID 監測 + DKA/AI/hypocalcemia/stress hyperglycemia management；Long COVID (PASC) ≥ 12 週 multi-axis surveillance。
RECOVERY 2020 dex 範式：mortality benefit + hyperglycemia management 必伴隨；basal-bolus + 30-50% increase from baseline。
CoviDIAB Hypothesis + 6 mo HbA1c surveillance：post-COVID 新發 DM real；SARS-CoV-2 + β-cell ACE2 機轉 + cytokine + steroid + chronic stress。
PASC ~10-30% + POTS ~20-30%：multidisciplinary management 必；lifestyle + symptom-targeted (β-blocker / ivabradine / midodrine) + 漸進性 recumbent exercise + 心理支持。
Vaccination strategy：vaccine-induced endocrinopathy 罕但 real；不應 contraindicate booster；multi-axis surveillance 個別化。

下一章 Ch 48（Final Chapter）等老闆指示。

本章 Williams 15e 原文 reference：Bornstein SR, Lazartigues E, et al. COVID-19 and Endocrine Disorders. In: Williams Textbook of Endocrinology, 15th ed. Elsevier; 2024.