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Abstract

We thank Fritzsche et al for their comments and report of an intriguing rare subset of a rare tumor; however, their final conclusion may not be quite accurate. Hypoglycemia in an adult patient without diabetes mellitus is an uncommon occurrence. Elderly medical inpatients are an exception, because in this group hypoglycemia is associated most strongly with sepsis or critical illness, may occur in up to 5.2% of patients, and was identified as an independent predictor of mortality.1Kagansky N. Levy S. Rimon E. et al.Hypoglycemia as a predictor of mortality in hospitalized elderly patients.Arch Intern Med. 2003; 163: 1825-1829Crossref PubMed Scopus (170) Google Scholar, 2Krinsley J.S. Grover A. Severe hypoglycemia in critically ill patients: Risk factors and outcomes.Crit Care Med. 2007; 35: 2262-2267Crossref PubMed Scopus (514) Google Scholar Only 71 hypoglycemic episodes were identified in a retrospective study of 37,898 new admissions (0.19%) and the major causes were end-stage kidney or liver disease, sepsis and alcohol,3Nirantharakumar K. Marshall T. Hodson J. et al.Hypoglycemia in non-diabetic in-patients: clinical or criminal?.PLoS ONE. 2012; 7: e40384https://doi.org/10.1371/journal.pone.0040384Crossref PubMed Scopus (41) Google Scholar although comorbidities were common. When other potential etiologies which are not rare (such as drugs, postprandial, or after gastric bypass surgery) also are considered, the statement “hypoglycemia in nondiabetic patients should raise the suspicion of a rare cause such as solitary fibrous tumors of the pleura” needs rephrasing. More so, because several important characteristics are common to non-islet cell tumors associated with hypoglycemia. First, mostly they are of mesenchymal origin (mesothelioma, solitary fibrous tumors of the pleura, sarcomas, etc) although a few cases of carcinomas and hematological malignancies have been reported. Second, the mechanism is the production of incompletely processed insulin-like growth factor-2 or “big”-IGF-2 by the tumor cells causing severe hypoglycemia with suppressed insulin and C-peptide levels; and finally, the tumors are generally large and clinically obvious when hypoglycemia occurs.4Skarulis M.C. Hirshberg B. Hypoglycemia in the adult.in: LeRoith D. Taylor S.I. Olefsky J.M. Diabetes Mellitus: A fundamental and clinical text. 3rd Edition. Lippincott Williams & Wilkins, Philadelphia2004: 1427-1440Google Scholar Thus, a hypoglycemic episode in a nondiabetic patient has several potential and more common causes before a hitherto unsuspected tumor such as the Doege-Potter syndrome can be considered. Hypoglycemia and Finger Clubbing—Consider Doege-PotterThe American Journal of MedicineVol. 126Issue 12PreviewSchattner et al1 describe a patient with increasing dyspnea in which the final diagnosis revealed a solitary fibrous tumor of the pleura. We read this report with great interest because we recently diagnosed and treated a comparable case in our institution. Full-Text PDF