05 December 2023
: Case report 
A Rare Skin Rash: Linezolid-Induced Purpuric Drug Eruption without Vasculitis in a Puerto Rican Man
Challenging differential diagnosis, Adverse events of drug therapy
Marilee A. Tirú-Vega1ABCDEF*, Natalie Engel-Rodriguez2BDE, Nicole Rivera-Bobé3BCDEF, Carla N. Cruz-Díaz
4DEF
DOI: 10.12659/AJCR.941725
Am J Case Rep 2023; 24:e941725
Table 1. Pertinent laboratory values of an 89-year-old male patient presenting with a drug-induced purpuric cutaneous eruption secondary to linezolid use. The table includes blood count, metabolic panel, and autoimmune, vasculitis, and infectious work-ups.
| Test | Result | Units | Reference range |
|---|---|---|---|
| Hemoglobin | 13.0 | g/dL | 12.6–17.8 |
| Platelets | 168 | ×10/µL | 155–371 |
| White blood cells | 11 400 | ×10/µL | 4.3–9.3 |
| Neutrophils | 56.9 | % | 34–74 |
| Eosinophils | 10.7 | % | 0–0.4 |
| Lymphocytes | 24.2 | % | 17–48 |
| Prothrombin time | 15 | Seconds | 11.8–15 |
| Partial thromboplastin time | 28.8 | Seconds | 22.4–38.3 |
| Internalized normalized ratio | 1.18 | 1.5 | |
| Blood urea nitrogen | 26.2 | mg/dL | 10–26 |
| Creatinine | 1.5 | mg/dL | 0.7–1.5 |
| Aspartate aminotransferase | 24 | U/L | 0–40 |
| Alanine aminotransferase | 34 | U/L | 0–45 |
| Alkaline phosphatase | 104 | U/L | 30–115 |
| Erythrocyte sedimentation rate | 13 | mm/h | 0–15 |
| C-reactive protein-high sensitivity | 11 H | mg/L | ≤5.0 |
| ANA | Negative | Negative | |
| C3 | 100 | mg/dL | 89–177 |
| C4 | 30 | mg/dL | 16–48 |
| Anti-dsDNA | 1 | IU/mL | <10.0 Negative |
| Anti-SS-A | <1.0 Negative | Al | <1.0 Negative |
| Anti-SS-B | <1.0 Negative | Al | <1.0 Negative |
| Anti-RNP | <1.0 Negative | Al | <1.0 Negative |
| Anti-Sm | <1.0 Negative | Al | <1.0 Negative |
| Rheumatoid factor | <10.0 | IU/mL | 0.01–14.0 |
| Cryoglobulins | Negative | Negative | |
| Hepatitis B surface antigen | Nonreactive | Nonreactive | |
| Hepatitis C virus (ELISA) | Nonreactive | Nonreactive | |
| Human immunodeficiency virus Ag/Ab | Nonreactive | Nonreactive | |
| ANA – antinuclear antibody; Anti-dsDNA – anti-double stranded DNA antibodies; Anti-SS-A – anti-Sjogren’s syndrome A antibodies; Anti-SS-B – anti-Sjogren’s syndrome B antibodies; Anti-RNP – anti-ribonucleoprotein; Anti-Sm – anti-Smith antibodies; C3 – complement 3; C4 – complement 4; ELISA – enzyme-linked immunosorbent assay; Ag – antigen; Ab – antibody. | |||