Diagnosis and Treatment > Signs and Symptoms
Research Support Center, Shizuoka General Hospital, Shizuoka, Shizuoka, Japan
Asahina Shinryoujo, Fujieda, Shizuoka, Japan
Search for other papers by Masato Kotani in
Google Scholar
PubMed
Research Support Center, Shizuoka General Hospital, Shizuoka, Shizuoka, Japan
Search for other papers by Naohisa Tamura in
Google Scholar
PubMed
Search for other papers by Tatsuhide Inoue in
Google Scholar
PubMed
Search for other papers by Issei Tanaka in
Google Scholar
PubMed
Summary
Type B insulin resistance syndrome is characterized by the presence of autoantibodies to the insulin receptor. We present a 57-year-old male admitted to a hospital due to body weight loss of 16 kg and hyperglycemia of 13.6 mmol/L. He was diagnosed with type B insulin resistance syndrome because the anti-insulin receptor antibodies were positive. We informed him that some hyperglycemic cases of this syndrome had been reported to be spontaneously remitted in 5 years, and he did not agree to be treated with high-dose glucocorticoids and/or immunosuppressive agents due to his concern for their adverse effects such as hyperglycemia and immunosuppression. He chose to be treated with insulin and voglibose, but fair glucose control could not be obtained. Six years later, he agreed to be treated with low-dose glucocorticoids practicable in outpatient settings. One milligram per day of betamethasone was tried orally and reduced gradually according to the values of glycated hemoglobin. After 30 months of glucocorticoid treatment, the anti-insulin receptor antibodies became undetectable and his fasting plasma glucose and glycated hemoglobin were normalized. This case suggests that low-dose glucocorticoids could be a choice to treat type B insulin resistance syndrome in outpatient settings.
Learning points:
-
Type B insulin resistance syndrome is an acquired autoimmune disease for insulin receptors.
-
This case suggested the possibility of long-lasting, low-dose glucocorticoid therapy for the syndrome as an alternative for high-dose glucocorticoids or immunosuppressive agents.
-
Since the prevalence of autoimmune nephritis is high in the syndrome, a delay of immunosuppressive therapy initiation might result in an exacerbation of nephropathy.
Search for other papers by Yasuhiro Oda in
Google Scholar
PubMed
Search for other papers by Masayuki Yamanouchi in
Google Scholar
PubMed
Search for other papers by Hiroki Mizuno in
Google Scholar
PubMed
Search for other papers by Rikako Hiramatsu in
Google Scholar
PubMed
Search for other papers by Tatsuya Suwabe in
Google Scholar
PubMed
Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Tokyo, Japan
Search for other papers by Junichi Hoshino in
Google Scholar
PubMed
Search for other papers by Naoki Sawa in
Google Scholar
PubMed
Department of Pathology, Graduate School of Medicine, Yokohama City University, Yokohama, Japan
Search for other papers by Kenichi Ohashi in
Google Scholar
PubMed
Search for other papers by Takeshi Fujii in
Google Scholar
PubMed
Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Tokyo, Japan
Search for other papers by Yoshifumi Ubara in
Google Scholar
PubMed
Summary
We report the renal histology of a 66-year-old man with hypertension, cardiovascular disease, and a 30-year history of type 2 diabetes mellitus with proliferative diabetic retinopathy, diabetic neuropathy, and diabetic foot status post toe amputation. Urinary protein excretion was 1.4 g/gCr, serum creatinine level 0.86 mg/dL, estimated glomerular filtration rate 69 mL/min/1.73 m2, and HbA1c 13–15%, despite using insulin. Light microscopy showed global glomerulosclerosis in 37% of the glomeruli, but the remaining glomeruli were intact. Significant polar vasculosis was present, while arteriolar sclerosis was mild. Electron microscopy revealed a thickened glomerular basement membrane, which is compatible with the early stage of diabetic glomerulopathy. The presented case was unique because glomerular changes seen typically in diabetes were not seen in the patient, despite the long-standing history of diabetes and diabetic comorbidities, while prominent polar vasculosis was found. Polar vascular formation helps preserve the glomeruli by allowing hyperosmotic blood bypass the glomeruli; this decreases intraglomerular pressure and minimizes glomerular endothelial damage.
Learning points:
-
A 66-year-old man with a 30-year history of type 2 diabetes mellitus with poor glycemic control underwent renal biopsy, which showed scarce glomerular changes typically seen in diabetic kidney disease and instead revealed significant polar vasculosis.
-
Past studies demonstrated that the increased small vessels around the vascular hilus in diabetic patients originated from the afferent arterioles and drained into the peritubular capillaries.
-
Polar vascular formation may preserve glomerular function by allowing the blood flow to bypass the glomeruli and decreasing the intraglomerular pressure, which minimizes endothelial damage of the glomerular tufts.
