Coombs Positive Thrombotic Thrombocytopenic Purpura in a Male Pediatric Patient: An Urgent Diagnostic Challenge

Abstract

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy often caused by deficiency of von Willebrand (vW) factor cleaving protease, ADAMTS-13, leading to large vW multimers and intravascular platelet aggregation. Hemolysis in TTP is mechanical and nonimmune mediated, thus Coombs testing is usually negative. We report a case of an adolescent with thrombocytopenia and Coombs positive anemia, diagnosed with Evans syndrome, but ultimately found to have TTP. TTP should be considered in children with thrombocytopenia and Coombs positive anemia who are refractory to steroids or develop signs of microangiopathy. Recognition of this presentation can lead to life-saving treatment with plasma exchange.

Diclofenac-induced thrombotic thrombocytopenic purpura with concomitant complement dysregulation: a case report and review of the literature

“…A false positive direct Coombs test has been reported with drugs like penicillin, cephalosporins, methyldopa, intravenous immunoglobulin (IVIG), HIV, malaria and conditions like lupus. A positive Coombs test may suggest immune hemolysis but other causes should be excluded as in our case [18–21].…”

Unusual Presentation of Thrombotic Thrombocytopenic Purpura in a Newly Diagnosed Pediatric Patient With Systemic Lupus Erythematosus in the Setting of MIS-C

“…8,9 Therefore, genetically predisposed patients, such as in the case presented (given the family history), who develop cytokine storm syndrome in COVID-19/MIS-C can theoretically be at risk of developing other autoimmune syndromes. 10 The chain of events is not fully clear in this case, but most likely, the patient encountered a COVID-19 infection around the time his father had which was followed by immune dysregulation and led to SLE onset.…”

“…Furthermore, it is well known that environmental triggers, such as viral infections, can trigger the activation of immune response with increased synthesis of cytokines, mainly tumor necrosis factor-α, IL-6 and IL-1β, IL-17, IL-18, in genetically predisposed patients 8,9. Therefore, genetically predisposed patients, such as in the case presented (given the family history), who develop cytokine storm syndrome in COVID-19/MIS-C can theoretically be at risk of developing other autoimmune syndromes 10. The chain of events is not fully clear in this case, but most likely, the patient encountered a COVID-19 infection around the time his father had which was followed by immune dysregulation and led to SLE onset.…”

“…To our knowledge, this is the only reported case with COVID-19 associated with TTP in the setting of new-onset SLE. Zenno and Richardson10 reported an adolescent case with TTP and positive DAT who was initially diagnosed with Evans syndrome but failed outpatient steroid management. His SLE screening markers were negative, and no concomitant infection was identified.…”

A Case Report of Cold Agglutinin Disease, Severe B12 Deficiency, and Pernicious Anemia: A Deadly Coincidence

“…The direct Coombs test tends to be negative; however, in our case, the direct Combs test was positive, making us believe autoimmune anemia might be involved. Nonetheless, cases of transient direct Coombs positive test on TMA have been reported, as was the case of Dan et al [ 18 ]; a transient positivity can be observed in up to 90% of patients with TMA secondary to neuraminidase-producing Streptococcus pneumonia [ 18 ], as well as the case of Zenno and Richardson [ 19 ], where a patient with TTP was found to have a positive Coombs test, which is a rare phenomenon [ 19 ].…”