Ketosis-resistant diabetes: a rare case in unlikely territory.

BACKGROUND Ketosis-resistant diabetes is a syndrome that has undergone numerous classification schemes in the past. In 1979, the National Diabetes Data Group (NDDG) introduced an association of malnutrition and diabetes. In 1985, the World Health Organization (WHO) created a new diabetes category called malnutrition-related diabetes mellitus (MRDM). MRDM consisted of two subclasses: fibrocalculous pancreatic diabetes (FCPD) and protein-deficient pancreatic diabetes (PDPD). Ketosis-resistant diabetes of the young (KRDY) was included in the subclass of PDPD. We report a rare case of a 37-year-old Sudanese immigrant with ketosis-resistant diabetes. CASE A previously healthy 37-year-old male presented with increased lethargy, polydipsia, polyuria and weight loss for the last seven to eight months. The patient had immigrated to the U.S. from his native country of Sudan about seven years earlier. He was hemodynamically stable. Physical exam was unremarkable with no evidence of retinopathy or neuropathy. Initial laboratory findings revealed a random blood sugar of 1,409 mg/dl and hemoglobin A1C of 17.8 percent. Urinalysis showed negative proteinuria, positive glycosuria, but only trace ketones were detected. Interestingly, the patient's serum ketones were negative. Arterial blood gas revealed PH 7.37, PCO2 47, P02 108 and HCO3 27. Further diagnostic workup revealed C-peptide 0.36, insulin antibodies less than 2, glutamic acid decarboxylase (GAD) antibodies less than 0.5, ICA 512 antibodies 2.9 and negative anti-islet cell antibodies. An abdominal ultrasound did not show any evidence of pancreatic calcifications or any pathology. Aggressive fluid resuscitation and intravenous insulin was initiated. The patient's hospital course was uncomplicated. He responded well to intravenous insulin drip and hydration. He was eventually transitioned to subcutaneous insulin. He was discharged three days later on a home regimen that included Lantus 28 units SQ at night, Novolog 8 units SQ with meals and a sliding scale with Novolog as needed. The patient's recent follow-up appointment revealed adequate glycemic control with HbA1C level of 7 percent. CONCLUSION Our patient did not meet criteria for either type 1 or type 2 diabetes mellitus. After a literature review of atypical etiologies of diabetes and comparing them to our patient, we concluded that the most likely diagnosis was KRDY. In light of a high influx of refugees and immigrants to the U.S., we should entertain. KRDY and other rare causes of diabetes mellitus in patients not satisfying criteria of either type 1 or type 2 diabetes.