14 November 2023: Articles
Immune Checkpoint Inhibitor-Induced Pure Red Cell Aplasia: A Review of 2 Cases in Metastatic Melanoma
Challenging differential diagnosis, Unusual or unexpected effect of treatment, Diagnostic / therapeutic accidents, Rare disease, Adverse events of drug therapy, Clinical situation which can not be reproduced for ethical reasons
Libardo Rueda Prada A* , Tatjana Gavrancic A , Miguel O. Cadena Sanabria D , Igor Dumic C , Kirk Bourgeois B , Rebecca L. King B , Yiyi Yan DDOI: 10.12659/AJCR.941789
Am J Case Rep 2023; 24:e941789
Table 1. Case 1. Summary of laboratory workup and timeline of hospital interventions.
| Time of presentation | First 24 h | Day 1 | Day 2 | Day 3 | Day 4 | 1 month | |
|---|---|---|---|---|---|---|---|
| Hemoglobin (g/dL) | 7.4 | 5.8 | 6.4 | 10.8 | 11.3 | 9.8 | 8.6 |
| Platelet count (×10/L) | 277 | 270 | 223 | 222 | 188 | 235 | 240 |
| White blood cell count (×10/L) | 4.9 | 5.2 | 5.7 | 4.4 | 4.0 | 3.6 | 3.5 |
| Reticulocyte (%) | 0.32 | 0.81 | 0.36 | 0.31 | 0.25 | 6.38 | |
| Absolute reticulocytes | 9.5 | 31.8 | 14.4 | 12.7 | 9.3 | 208.6 | |
| Additional anemia workup | Iron 85 mcg/dL. Total iron binding capacity 188 mcg/dL. TSAT 45%. Ferritin 2307 mcg/L. B12 level >1400 ng/L. Folate level 10.0 mcg/L. Fecal occult blood test negative. Normal peripheral blood flow cytometric immunophenotyping. Parvovirus B19 serology and PCR negative | ||||||
| DIC workup | D-dimer 2619 ng/mL. Fibrinogen 349 mg/dL. PT 13.9 sec. INR 1.3. aPTT 29 sec | ||||||
| Hemolysis workup | No schistocytes seen in peripheral blood smear. LDH 794 U/L (chronically elevated 624–781 U/L over last year). Total bilirubin 0.6 mg/dL. Haptoglobin < 14 mg/dL. Direct Coombs negative | ||||||
| Reference ranges: Reticulocyte (%) 0.60–2.71. Absolute reticulocyte 30.4–110.9×10/L. Iron 35–145 mcg/dL. Total iron binding capacity 250–400 mcg/dL. TSAT 14–50%. Ferritin 11–307 mcg/L. B12 level 180–914 ng/L. Folate level ≥4.0 mcg/L. D-dimer ≤500 ng/mL. Fibrinogen 200–393 mg/dL. PT 9.4–12.5 sec. INR 0.9–1.1. aPTT 25–37 sec. LDH 122–222 U/L. Total bilirubin ≤1.2 mg/dL. Haptoglobin 30–200 mg/dL. DIC – disseminated intravascular coagulation; LDH – lactate dehydrogenase; PRBC – packed red blood cells; PT – prothrombin time; aPTT – activated partial thromboplastin time; TSAT – transferrin saturation. | |||||||