Symptoms suggesting urolithiasis mask a life-threatening ailment
Photo: Initially, the clinical support team suspected that the young man may have a kidney stone.
Mr. R, a 30-year-old black man, presented to our clinic noting that he had experienced fever, chills and sweats accompanied by nausea and vomiting, all of which started two days earlier. Mr. R had no diarrhea or abdominal pain, but he did complain of fatigue. He also mentioned a steady, dull pain in his back.
When asked, Mr. R noted no dys uria, or urinary frequency or urgency. His urine was darker than normal, and he noted occasional gross hematuria (but no nocturia). He reported no headache, confusion, cough, shortness of breath or palpitations. No recent weight changes were reported. Mr. R's vomiting was significant enough that he could only tolerate popsicles and small sips of water, but there was no hematemesis.
Mr. R's history is questionable for nephrolithiasis. He has no incidence of renal, bladder or prostate disease, and until this episode, he had been healthy except for periodic migraine headaches. His family history is significant for nephrolithiasis. Mr. R is married with one daughter. In his job as a mortician, he routinely uses embalming chemicals. He admits to occasional marijuana use and smokes cigarettes but does not consume alcohol.
Upon presentation, the patient was afebrile and had a BP of 142/82 mm Hg. He was at a healthy weight. Mr. R's head and neck exam was unremarkable; his lung sounds were normal, and his heart rhythm was regular, expressing no click, murmur or rub.
The patient's abdomen showed no scarring, exhibited normoactive bowel sounds, and was tympanic to percussion. The abdomen was nontender and soft throughout without organomegaly.
There were no hernias or costovertebral angle tenderness. In addition, Mr. R had no evident edema about the extremities, and his skin was mildly diaphoretic but without rash, ecchymosis or petechiae. Mr. R exhibited no focal neurologic deficits.
3. Laboratory Data and Diagnosis
A urinalysis dip exhibited blood and protein but was otherwise normal. Mr. R was sent for a CT scan with renal stone protocol to rule out nephrolithiasis. Because of the fever and vomiting, a basic metabolic panel and complete blood count were obtained: glucose 118 mg/dL; blood urea nitrogen and creatinine 33.4 mg/dL and 1.8 mg/dL, respectively; sodium 135 mEq/L; potassium 3.5 mEq/L; chloride 98 mEq/L.
Bicarbonate and calcium were normal. His white blood cell count was 6.84 x 103/µL, hemoglobin 11.1 g/dL, and hematocrit 31.5%, and platelets were verified to be 14.8 x 103/µL.
The severe thrombocytopenia prompted an immediate hospital admission. To complete the workup, the following tests were performed: a lactate dehydrogenase (LDH) and antinuclear antibody test with reflex; prothrombin time; partial thromboplastin time; international normalized ratio; lupus anticoagulant, and anticardiolipin panel.
The LDH returned >1,000 U/L (reference range 80-230). The remaining labs were normal. Hepatitis and HIV panels were later found to be negative. A STAT pathology review of Mr. R's peripheral smear revealed normochromic, normocytic anemia, thrombocytopenia and a moderate amount of schistocytes. Thrombotic thrombocytopenic purpura (TTP) was diagnosed.