SESSION TYPE: Critical Care Case Report Posters
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy characterized by hemolytic anemia and thrombocytopenia. Common microthrombi-related ischemic symptoms include cerebral, renal, cardiac, and gastrointestinal; reports indicate that dyspnea is an uncommon complaint and severe, life-threatening hypoxemia in the setting of TTP is extremely rare (1).
CASE PRESENTATION: A 24 year old black male developed altered mental status while exercising, culminating in syncope. Paramedics found him awake but confused. In the emergency department, patient was intubated due to altered mental status. The blood pressure was 241/137, oxygen saturation of 100%with clear lungs. Hemoglobin was 9.3g/dL, platelet count 46,000/ mm3, and peripheral smear showed 30 schistocytes/HPF. CT brain showed diffuse cerebral edema; MRI revealed bilateral cortical and leptomeningeal enhancement. Upon arrival to the tertiary center, patient remained hypertensive 168/110, heart rate 140 with temperature 38.1 C. Platelet count decreased to 22,000/ mm3, LDH 2105 u/L, and blood, urine and CSF studies were all negative for infection. Shortly after arrival gradual worsening hypoxemia ensued. Chest x-ray showed no infiltrate. PaO2 on blood gas was 42-45 mmHg despite paralytics and PEEP 15-20cmH2O on the ventilator; inhaled nitric oxide was ordered to bedside. Emergent plasma-exchange and steroids were instituted for presumptive TTP. Oxygenation improved with plasma-exchange and extubation occurred early morning day 3. Platelet counts had normalized to 210,000/mm3. Malignant hypertension was considered as the etiology of the thrombotic microangiopathy. However, significant fall of platelet counts from day 6 through day 8 of hospitalization with lack of hypertensive pressures necessitated repeat plasma-exchange and course of steroids resulting in rapid improvement and remission. ADAMST13 levels were <5% with presence of inhibitor.
DISCUSSION: A few case reports and series have proposed respiratory failure as a feature of TTP (2-3). However, confounding factors included co-diagnoses known to mimic findings of TTP and respiratory failure. A large patient registry indicates that on presentation, pulmonary symptoms are infrequent and significant infiltrates on chest x-ray are rare (1).
CONCLUSIONS: Our patient met clinical and laboratory criteria for the diagnosis of TTP having severe hypoxic respiratory failure without significant pulmonary infiltrates. We hypothesize that our patient’s respiratory failure was related to occlusion of the pulmonary microvasculature with resolution as appropriate therapy was provided. Profound hypoxemia without pulmonary infiltrates has not been widely reported as part of the TTP symptom complex.
1) George, James. Blood 2010;116:4060-4069
2) Panoskaltsis et al. Am Journal of Hematology 2000; 65:50-55
3) Chang et al. Am Journal Medical Sciences 2001; 321(2):124-128
DISCLOSURE: The following authors have nothing to disclose: Timothy Nokes, Ahmed Awab, James George, Qiaofang Chen
No Product/Research Disclosure InformationUniversity of Oklahoma Health Science Center, Oklahoma City, OK