Thrombocytopenia Induced by Diazoxide in a Patient with an Insulinoma

Abstract

A 24-year-old healthy woman presented at our hospital due to hypoglycemia. A fasting test provoked spontaneous hypoglycemia, and contrast-enhanced abdominal computed tomography revealed a pancreatic tumor. We diagnosed her with insulinoma and initiated diazoxide treatment to prevent hypoglycemia. After 13 days of treatment, she experienced nasal bleeding, and her platelet count decreased from 186,000/μL to 28,000/μL. The thrombocytopenia was ameliorated five days after diazoxide was discontinued. Although diazoxide has hyperglycemic effects associated with decreased insulin secretion, diazoxide-induced thrombocytopenia is rare. A complete blood count should be obtained periodically in patients receiving treatment with diazoxide.

The difficult management of persistent, non‐focal congenital hyperinsulinism: A retrospective review from a single, tertiary center

“…However, hypertrophic cardiomyopathy may be the result of the anabolic effects of hyperinsulinism itself and octreotide has been used to reduce hypertrophic cardiomyopathy in other patients . Thrombocytopenia as well as neutropenia are rare, but recognized as side effects to treatment with diazoxide . None of our non‐focal patients died, developed necrotizing enterocolitis, glucagon‐induced migratory necrolytic erythema, or had other adverse events described elsewhere in the treatment of CHI …”

Clinical outcomes of 20 Japanese patients with insulinoma treated with diazoxide

“…It is notable that thrombocytopenia was observed in 5 of the 20 patients (25%) treated with diazoxide in this case series. Although several cases have been reported on diazoxide-induced thrombocytopenia [7,13,14], hematological adverse effects are rare not only in patients in insulinoma [4] but also in those with congenital hyperinsulinism [15], who are treated with diazoxide as the first choice. In terms of drug-induced thrombocytopenia, it has been proposed that the sensitizing drugs typically contain structural elements that enable them to bind to both the antibody and platelet surface proteins [16].…”

“…This retrospective study evaluated the medical records of patients with insulinoma who were admitted during 2008-2016 to Tokyo Medical and Dental University Hospital, Yokohama City Minato Red Cross Hospital and Tokyo Metropolitan Tama Medical Center. One case has been reported [7]. Patients with diabetes who had developed hypoglycemia secondary to insulin or oral hypoglycemic agent intake, hypoglycemia due to insulin antibodies, hypopituitarism, or hypoadrenalism were not included in the study.…”

Thrombocytopaenia: a serious side effect of diazoxide

“…Known common side effects include hirsutism and fluid retention 5. Although severe thrombocytopaenia with increased bleeding tendency was already described as a side effect of diazoxide in 1967, measurement of platelet count after the start of this drug is not part of routine clinical care 2. Consequently, in this case, the severe increased bleeding tendency was the presenting symptom of the thrombocytopaenia due to drug-induced immune thrombocytopaenia.…”

“…Laboratory investigations showed severe thrombocytopaenia (platelet count on repeated measurements 5–8×10 9 /L) without anaemia and neutropenia. As drug-induced immune thrombocytopaenia had been described after exposure to diazoxide and HCT in some case reports, the possibility of drug-induced immune thrombocytopaenia was considered 1–4. Diazoxide and HCT were stopped and feeding by nasogastric tube continuously was restarted.…”