Endocrine Abstracts

Introduction: The treatment of thyroid diseases with thionamides can cause agranulocytosis a potentially fatal side effect. The manifestations resulting from such a condition include, in most cases, infections that, if not treated immediately, have a high risk of septicemia. Therefore, the clinical presentation includes fever of unknown origin and infections such as pneumonia, tonsillitis, and abscesses. Most patients who do not receive immediate medical intervention progress to septicemia, a fact that shows the relevance of early diagnosis and adequate management

Case report: A 38-year-old female patient had Chronic Myeloid Leukemia without follow-up and treatment. She developed severe neutropenia induced by thionamide used to control hyperthyroidism. Laboratory tests performed on admission at the Hospital showed Hb 8.6 g/dl, pancytopenia with worsening leucopenia: leukocytes 720/mm3, absolute segmented count 9 mm3, 0/mm3 (zero) basophils, 0 /mm3 (zero) blasts, and 670/mm3 lymphocytes, TSH 0.029 mU/l (normal 0.4-4.5 mU/l) and free T4 4.93 ng/dl (normal 0.7-1.8 ng/dl). Autoantibodies against TSH receptor (TRAb) were negative The absence of evidence of transformation into accelerated and blastic phases of Chronic Myeloid Leukemia, positive clinical response, resolution of neutropenia 8 days after the suspension of thionamides, and the presence of a 5/1 Myeloid: Erythroid ratio in bone marrow biopsy, suggested the previous destruction of neutrophils, with recovery after drug discontinuation.

Conclusion: The state of severe neutropenia is attributable to drugs in 70 to 90% of cases. The absence of evidence of transformation for the accelerated and blast phases of Chronic Myeloid Leukemia, positive clinical response associated with resolution of neutropenia after thionamide withdrawal and the presence of a 5/1 Myeloid: Erythroid ratio in bone marrow biopsy, suggesting the previous destruction of neutrophils, with recovery after discontinuation of the drug evidence the differential diagnosis of thionamide-induced agranulocytosis overlying the underlying diagnosis of hematological disease. The manifestations resulting from such a condition include, in most cases, infections that have a high risk of progressing to septicemia. After resolution of the condition, which occurs between 3-14 days after the drug is discontinued, definitive treatment for hyperthyroidism should be considered, usually with radioactive iodine or surgery.