title: Didactic lessons from the serum lactate dehydrogenase posttransplant: a clinical vignette.
abstract: Posttransplant lymphoproliferative disorder (PTLD) is a serious complication after solid organ transplantation. An elevated serum lactate dehydrogenase (LDH) is a marker of PTLD activity. We report the case of a 58-year-old female renal transplant patient with a prior history of extranodal PTLD, which developed 19 years after a second transplant. She was successfully treated with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) and maintained subsequently on sirolimus and prednisone. She presented 3 years later with fever, dyspnea, cough, lung infiltrates and elevated serum LDH concerning for recurrence of PTLD. Bronchoscopy revealed Pneumocystis carinii (jiroveci) pneumonia. The patient was treated with trimethoprim-sulfamethoxazole, but developed nausea and was converted to dapsone. The patient was readmitted 4 weeks later with increasing dyspnea and hypoxemia and found to have a methemoglobin level of 16%. Dapsone was discontinued with resolution of all symptoms. We discuss the diagnostic and clinical challenges in this complex case.
authors.affiliation: Barnes-Jewish Hospital, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: R
authors.initials: R
authors.lastname: Boothpur
authors.forename: D C
authors.initials: DC
authors.lastname: Brennan
mesh_terms: D000890:Anti-Infective Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D003622:Dapsone / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects*; D007770:L-Lactate Dehydrogenase / Q000097:blood*; D008232:Lymphoproliferative Disorders / Q000175:diagnosis*; D008875:Middle Aged; D016720:Pneumocystis Infections / Q000188:drug therapy*; D011183:Postoperative Complications / Q000175:diagnosis* / Q000188:drug therapy; D016896:Treatment Outcome; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D015415:Biomarkers; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D003622:Dapsone; D007770:L-Lactate Dehydrogenase