Table 1 Comparison of four similar unusual cases of pseudothrombotic thrombocytopenic purpura caused by vitamin B12 deficiency presenting with renal failure and a lack of macrocytosis
Clinical characteristics | Patients series (Author and reference) | ||||
|---|---|---|---|---|---|
Present case report | Kandel et al. [12] | Walter et al. [13] | Dalsania et al. [14] | Garderet et al. [15] | |
Gender/Age | M/46 | F/86 | F/77 | M/48 | M/38 |
Hemoglobin (g/L) [140–180] | 36 | 32 | 55 | 50 | 45 |
MCV (fl) [80–99] | 87 | 127 | 120 | 80.2 | 90 |
WBC/neutrophil (× 109/L) [4–11/1.5–7.5] | 2.52/0.59 | 6.5/− | 5.9/− | 6.3/− | 2.2/− |
Platelets (×  109/L) [140–440] | 46 | 59 | 40 | 38 | 5 |
Creatinine (μmol/L) [59–103] | 176.8 | 168 | 300.6 | 97.2 | Normal |
Corrected reticulocyte count/Absolute reticulocyte count (× 109/L) [0.5–2/25–75] | 0.18/8.7 | 1.6/− | 1.2/− | 0.23/13 | −/10 |
Schistocytosis | Present | Present | Present | Present | Present |
LDH (μkat/L) [2.25–3.76] | 24.6 | 118.2 | 66.5 | 150.1 | 323.7 |
Total/direct bilirubin (μmol/L) [<  24/< 5.1] | 17.1/− | – | 63.3/17.1 | 20.5/5.1 | 205.3/85.5 |
Haptoglobin (mg/L) [300–2000] | <  1 | 140 | Undetectable | <  100 | <  100 |
Coombs test | Negative | Negative | Negative | Negative | Negative |
Serum B12 (pmol/L) [145–569] | <  36.9 | 28 | Undetectable | 352.7 | Undetectable |
Methylmalonic acid level (μmol/l) [0–0.4] | Not performed | 0.753 | Not performed | 25,417 | Not performed |
Neurological symptoms | None | Present | Present | None | None |
TPE | NO | NO | YES | YES | YES |