Swing for the HIT: Early Diagnosis and Management of Heparin Induced Thrombocytopenia (HIT) in Inpatient Rehabilitation

Case Diagnosis: 69F admitted after thoracic decompression with HIT-positive deep vein thrombosis (DVT)

Case Description or Program Description: 69F with history significant for renal cell carcinoma status post nephrectomy was admitted to acute care with severe back pain. Work up reported T11 osteolytic body fracture with extension causing cord compression. Neurosurgery conducted a T9-L1 decompression and fusion with tumor resection and embolization. Hospital course was uncomplicated, and she was discharged to inpatient rehabilitation. On day five, routine labs revealed thrombocytopenia of 112, down from 245 on admission. Labs were remarkable for a mild, stable leukocytosis and anemia. Patient had no infectious symptoms and vital signs were normal. Physical exam had normal cardiac and pulmonary findings, negative bilateral leg swelling, and clean surgical site. She had fatigue and dyspnea on exertion without desaturation, which she attributed to her anemia.

Day six, labs revealed stable thrombocytopenia. 4T score was 4, indicating intermediate risk for HIT. Heparin was discontinued and HIT panel reported a positive antibody, so hematology was consulted. Dopplers reported an occlusive thrombus of the left external iliac and common femoral veins extending to popliteal vein. She developed mild left leg swelling. Hematology recommended Argatroban and evaluation for thrombectomy. She was transferred to acute care.

Setting: In-patient rehabilitation hospital

Assessment/Results: Although thrombocytopenia is often benign, a greater than 50% decrease in platelets should raise red flags for consumptive process of platelets, particularly in setting of malignancy. With malignancy, increased inflammatory state and endothelial damage from surgery, she was in a hypercoaguable state per Virchow's triad. 4T scoring resulted in an early diagnosis while patient was mildly symptomatic. Delays may have resulted in further DVT expansion or pulmonary embolism.

Discussion (relevance): This is one of few cases of HIT diagnosed during inpatient rehabilitation and the only with mild clinical symptoms.

Conclusions: Early recognition and hematology consultation is critical to managing HIT in inpatient rehabilitation.