Taglietti et al. Journal of Medical Case Reports 2010, 4:332 http://www.jmedicalcasereports.com/content/4/1/332 C A S E R E P O R T JOURNAL OF MEDICAL CASE REPORTS Open Access Acute hepatocellular and cholestatic injury during therapy with hydrochlorothiazide - clinicohistopathologic findings: a case report Fabrizio Taglietti1*, Franca Del Nonno2, Andrea Baiocchini2, Laura Falasca3, Stefano Pieri4, Alessandro Capone1, Elisabetta Grilli1, Pierangelo Chinello1, Nicola Petrosillo Abstract Introduction: Hydrochlorothiazide and thiazide-like diuretics are considered first-line drugs for initial therapy in uncomplicated arterial hypertension. Acute cholecystitis is a well-known complication during treatment with thiazide, and these drugs are also reported to be followed by pronounced insulin resistance. Case presentation: We describe a case of acute cholestatic hepatitis in a 68-year-old Caucasian man who was receiving olmesartan and hydrochlorothiazide for arterial hypertension. From the clinical and histologic findings, we diagnosed him as having hepatocellular-cholestatic injury and a disorder of glucose metabolism in the liver. To the best of our knowledge, no histopathologic description of hydrochlorothiazide hepatotoxicity has previously been documented in the literature. Conclusion: In the differential diagnosis of cholestatic hepatitis, clinicians should be aware of the possibility of liver damage in patients receiving hydrochlorothiazide therapy. Introduction Thiazide diuretics are first-line and low-cost drugs used to treat uncomplicated arterial hypertension [1]. They were originally synthesized in an effort to enhance the potency of inhibitors of carbonic anhydrase. However, unlike carbonic anhydrase inhibitors, which primarily increase Sodium Bicarbonate (NaHCO3) excretion, thia- zides were found predominantly to increase Sodium Chloride (NaCl) excretion, an effect shown to be inde- pendent of carbonic anhydrase inhibition. The major concerns about their use arise from their tendency to cause hypokalemia, impair glucose toler- ance, and increase serum cholesterol and uric acid. Similar to loop diuretics, the most serious adverse events are related to abnormalities of fluid and electro- lyte balance [2]. The most common adverse events of thiazide diuretics include vertigo, headache, paresthesias, xanthopsia, * Correspondence: taglietti.f@gmail.com 1II Division of Infectious Diseases, Istituto Nazionale per le Malattie Infettive, Istituto di Ricovero e Cura a Carattere Scientifico ‘Lazzaro Spallanzani’, Rome, Italy Full list of author information is available at the end of the article weakness, anorexia, nausea, vomiting, cramping, diar- rhea, constipation, cholecystitis, pancreatitis, blood dys- crasias, photosensitivity, and skin rashes [2-7]. Thiazide diuretics also decrease glucose tolerance, and latent diabetes mellitus may be unmasked during ther- apy. The mechanism behind the impaired glucose toler- ance is not completely understood, but appears to involve reduced insulin secretion and alterations in glu- cose metabolism [8]. Thiazide diuretics also may increase plasma levels of low-density lipoprotein cholesterol, total cholesterol, and total triglycerides. Hepatotoxicity by hydrochlorothiazide (HCTZ) therapy is an uncommonly adverse event rarely described, and only clinically [9]. We describe a clinical case of HCTZ-induced acute cholestatic hepatitis associated to alterations of the glu- cose metabolism inside the liver. Case presentation A 68-year-old Caucasian man was admitted to our Infectious Diseases Unit with a ten-day history of jaun- dice, asthenia, nausea, vague right upper quadrant abdominal pain and hyperchromic urine. Twenty days © 2010 Taglietti et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.