A 39-year-old Sudanese male presented to the emergency room with fever, jaundice, and decreasing level of consciousness (inability to recognize relatives) for 7 days. There were no associated symptoms or past medical history. The following laboratory values were obtained: white blood cell (WBC) count, 8.6 × 109/L; hemoglobin (Hb), 67 g/L; platelet (PLT) count, 8 × 109/L; creatinine, 121 μmol/L; prothrombin time and partial thromboplastin time, normal; lactate dehydrogenase level (LDH), 1947 U/L; increased reticulocyte count; and blood smear showing schistocytes. A urine analysis showed the following: blood, +4; pH 5.5; protein, +2; red blood cell count, 15–20; WBC count, 1; and specific gravity, 1.0170. The presence of microangiopathic hemolytic anemia, thrombocytopenic purpura, neurologic abnormalities, fever, and renal disease confirmed the patient’s diagnosis.
The patient was admitted with a presumptive diagnosis of TTP for plasma exchange. He received a total of 28 sessions of plasmapheresis. His LDH level decreased to 534 U/L, Hb increased to 87 g/L, and PLT count increased to 36 × 109/L. Ten days later, his LDH rose to 1270 U/L, with Hb of 105 g/L and PLT count of 14 × 109/L. The patient was started on vincristine and rituximab with a high dose of dexamethasone. The patient was also started on cryoprecipitate supernatant because of the suboptimal response to plasmapheresis with fresh frozen plasma. This was thought to be a relapse of TTP; the condition was considered and managed as resistant TTP. Two days later, intravenous immunoglobulin (full dose) was started. Despite the treatment for resistant TTP, the patient worsened, requiring ICU (intensive care unit) admission because of the development of uncontrolled seizures, which required intubation and ventilation. The patient developed left-sided weakness and hypotension. He was started on vasopressors. Treatment with antibiotics and then antifungal therapy commenced; the case was labeled as refractory TTP. Repeated brain computed tomography scans were normal.
During this process, the creatinine kinase (CK) levels increased to >50,000 U/L, with worsening kidney function and decreased urine output. Acute renal failure in this patient was diagnosed according to the RIFLE (risk, injury, failure, loss, end stage) criteria: a rise in creatinine of more than three-fold, and urine output < 0.3 mL/kg/h over 24 hours. Urine alkalanization was started when creatine phosphokinase (CPK) started rising to a target urine pH of 8, with several fluid boluses targeting a urine output of >200 mL/h. Mannitol was used for 24 hours only. The serum calcium concentration was monitored on a daily basis throughout the patient’s stay in the ICU and after his discharge to a step-down unit. Continuous venovenous hemodialysis started, although the CPK levels did not decrease for 5 days. After maintaining the patient on dialysis for 2 weeks, the patient started to improve clinically and was more alert, with a CK level of 5360 U/L and PLT count of 95 × 109/L (see ).
Daily alteration of creatine, CPK, and Ca in association with CVVHD.
All possible differential diagnoses for rhabdomyolysis were investigated, including metabolism, viral serology, bacterial levels, toxins, and drugs. Compartment syndrome was ruled out because of the sustained CPK release.
The difficulty in weaning the patient from the ventilator stemmed from critical illness polyneuropathy and the consequences of the tracheostomy. The patient was eventually weaned from the ventilator. He was conscious and alert, with residual weakness/paresis of the lower limbs, which was managed with physiotherapy. The patient continued to require intermittent hemodialysis thrice every week.