| Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access |
| Article copyright, the authors; Journal compilation copyright, J Med Cases and Elmer Press Inc |
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Case Report
Volume 17, Number 2, February 2026, pages 75-79
Intravenous Thiamine-Induced Thrombocytopenia in a Patient With Chronic Adrenal Insufficiency
Tables
| Parameter | Value | Reference range |
|---|---|---|
| WBC: white blood cell; MCV: mean corpuscular volume. | ||
| Hemoglobin | 13.3 g/dL | 12.5 - 16.5 g/dL |
| WBC | 7.5 × 109/L | 4.0 - 11.0 × 109/L |
| Platelets | 225 × 109/L | 150 - 450 × 109/L |
| MCV | 96 fL | 78 - 98 fL |
| Reticulocytes | 1.2% | 0.5-2.5% |
| Day | Intervention | Platelet count (× 109/L) | % Change | CTCAE grade |
|---|---|---|---|---|
| 0 (baseline) | Before thiamine (day of initiation) | 225 | 0 | 0 |
| 1 | Day 1 after thiamine started | 150 | -33% | 0 |
| 2 | Day 2 - thiamine continued | 110 | -51% | 0 |
| 3 | Day 3 - thiamine continued | 86 | -62% | Grade 1 |
| 4 | Day 4 - thiamine continued | 63 | -72% | Grade 2 |
| 5 | Day 5 - thiamine continued | 48 | -79% | Grade 3 |
| 6 | Day 6 - thiamine stopped | 65 | +35% | Grade 2 |
| 7 | Day 7 - post-cessation | 88 | +83% | Grade 2 |
| 8 | Day 8 - post-cessation | 132 | +175% | Grade 1 |
| 14 | Day 14 - follow-up (2 weeks) | 265 | Complete recovery | 0 |
| Condition | Investigations | Results | Conclusion |
|---|---|---|---|
| DIC: disseminated intravascular coagulation; HIT: heparin-induced thrombocytopenia; TTP: thrombotic thrombocytopenic purpura; HUS: hemolytic uremic syndrome; HIV: human immunodeficiency virus; Hep C: hepatitis C virus; Hep B: hepatitis B virus; RBC: red blood cell; CRP: C-reactive protein; PT: prothrombin time; aPTT: activated partial thromboplastin time; INR: international normalized ratio; ANA: antinuclear antibody; ESR: erythrocyte sedimentation rate; LDH: lactate dehydrogenase; CBC: complete blood count; HIV Ag/Ab test: human immunodeficiency virus antigen/antibody test; anti-HCV antibody: hepatitis C virus antibody; HBsAg: hepatitis B surface antigen; anti-HBc: hepatitis B core antibody; anti-HBs: hepatitis B surface antibody; AST: aspartate aminotransferase; ALT: alanine aminotransferase; GGT: gamma-glutamyl transferase. | |||
| Sepsis | Vitals, CRP, blood cultures | BP 135/88, CRP 0.88 mg/dL, cultures negative | Excluded |
| DIC | PT, aPTT, INR, fibrinogen, D-dimer | PT 10 s, aPTT 26 s, INR 0.9, Fib 360 mg/dL, D-dimer 0.50 | Excluded |
| HIT | Heparin exposure, 4T score | No heparin exposure, 4T score = 0 | Excluded |
| Autoimmune | ANA, Coombs, ESR | ANA negative, Coombs negative, ESR 18 | Excluded |
| TTP/HUS | LDH, haptoglobin, schistocytes | LDH 160 IU/L, haptoglobin 52 mg/dL, no schistocytes | Excluded |
| Bone marrow | CBC, peripheral smear | Isolated thrombocytopenia, normal morphology | Excluded |
| HIV infection, Hep C, and Hep B | HIV Ag/Ab test, anti-HCV antibody, HBsAg, anti-HBc, and anti-HBs | Negative, negative, negative, negative, and positive | Excluded and vaccinated Hep B |
| Liver function test | AST, ALT, alkaline phosphatase, GGT, total bilirubin | 34 U/L, 38 U/L, 56 U/L, 22U/L, 1.1 mg/dL | Normal test |
| Renal function and electrolytes | Creatinine, urea, Na, K, Cl, Mg, Ca | 1.1 mg/dL, 22 mg/dL, 134 mmol/L, 3.7 mmol/L, 99 mmol/L, 1.9 mg/dL, 9.3 mg/dL | Borderline test |
| Vitamin B12 and folate | Serum values of vitamin B12 and folate | 369 pmol/L, 14 ng/mL | Normal |
| RBC count | RBC count | 5.1 × 106/µL | Normal |