Hydroxychloroquine-induced cardiomyopathy that presented as pulmonary hypertension: a newly noted complication.

We examined a 63-year-old woman with progressive dyspnea. Two years prior to admission to our hospital, she had been diagnosed with rheumatoid arthritis and treated with hydroxychloroquine (HCQ) with a cumulative dose of 164 g. In addition, 2 months earlier, she had been diagnosed with connective tissue disease-related pulmonary artery hypertension. We performed an electrocardiogram and noted complete atrioventricular block. A transthoracic echocardiogram showed pulmonary hypertension. Due to the unclear nature of the pulmonary hypertension, we performed cardiac catheterization and right ventricular endomyocardial biopsy. Cardiac catheterization revealed that pulmonary hypertension was due to left ventricular dysfunction. Electron microscopy of the cardiac biopsy demonstrated a curvilinear body, diagnostic of HCQ toxicity. Thus, we diagnosed pulmonary hypertension owing to left heart disease and complete atrioventricular block that resulted from HCQ toxicity. Insertion of a permanent pacemaker and discontinuation of HCQ dramatically improved the disease state. This is the first report of this type of cardiac complication with HCQ; it raises the awareness that HCQ may cause cardiac complications despite a small cumulative dose relative to doses reported in other cases. Furthermore, we emphasize that cardiac catheterization played a critical role in the differential diagnosis from pulmonary hypertension associated with connective tissue disease.

Mucosal schwann-cell hamartoma diagnosed by using an endoscopic snare polypectomy.

Colorectal polyps of mesenchymal origin are a rare group of colorectal disorders. A "mucosal Schwann-cell hamartoma," which is one type of polypoid lesion that originates from the mesenchyme, is a newly-proposed disease entity to be distinguished from the neurofibromas found in type-1 neurofibromatosis. This lesion is composed of pure Schwann-cell proliferation in the lamina propria and shows diffuse immunoreactivity for the S-100 protein. We report a case of a polypoid lesion of the colon with the features of this recently-proposed disease entity.

Recurrent Insulin Autoimmune Syndrome Caused by α-Lipoic Acid in Type 2 Diabetes.

Insulin autoimmune syndrome (IAS) is characterized by spontaneous hypoglycemia caused by insulin autoantibodies in the absence of exogenous insulin administration. Some drugs containing sulfhydryl compounds are known to initiate the onset of IAS. A 67-year-old female who had diabetes for 5 years visited the outpatient clinic at our institution due to diabetic peripheral polyneuropathy. She was prescribed α-lipoic acid (ALA), which contains two sulfur atoms. Two weeks later, she complained of recurrent hypoglycemic symptoms. We detected a high level of insulin and high titers of insulin autoantibodies. Her human leukocyte antigen (HLA) genotype included the DRB1*0406 allele, which indicates a high level of susceptibility to IAS. She was treated with prednisolone. After this episode, she experienced two more hypoglycemic events after taking ALA for diabetic neuropathy in other hospitals. As ALA can be used to treat diabetic peripheral polyneuropathy, physician discretion is advised based on the possibility of IAS due to ALA in diabetic patients.