title: Lymphocytic colitis associated with lansoprazole treatment.
abstract: BACKGROUND
  There have been several reported cases of lansoprazole-associated collagenous colitis (CC) reported in the literature but only 1 reported case of lansoprazole-associated lymphocytic colitis (LC) in the literature. Both CC and LC are considered inflammatory bowel diseases, but they are distinctly classified based on the condition of the colon, which is typically confirmed through biopsy.
  
  
  METHODS
  A 52-year-old white male (Patient 1), with a height of 178 cm and weight of 75 kg, presented to Gazi University Hospital, Ankara, Turkey, with a 3-month history of abdominal pain and nonbloody, watery diarrhea. The patient reported receiving PO lansoprazole 30 mg/d to treat heartburn ~1 week prior to the onset of diarrhea. The patient's medical history revealed that he did not have any preexisting conditions, other than gastroesophageal reflux disease (GERD) for which lansoprazole was prescribed. The medical history report also revealed that the patient was not receiving any concomitant medications or treatments at the time. A colon biopsy confirmed LC. Additionally, a 43-year-old white female (Patient 2), with a height of 168 cm and weight of 61 kg, presented to the same facility with a 6-month history of nonbloody, watery diarrhea and mild lower abdominal cramping. The patient reported that initial onset began ~2 months after receiving a 10-day Helicobacter pylori eradication combination treatment regimen that included lansoprazole, amoxicillin, and clarithromycin, followed by lansoprazole monotherapy to treat GERD. The patient's medical history revealed no other concomitant medications were being adminstered at the time. A colon biopsy confirmed LC.
  
  
  CONCLUSIONS
  A search of the literature using the MEDLINE database and all relevant English-language articles with key words lansoprazole and lymphocytic colitis, found that there were several cases of lansoprazole-associated CC reported and 1 reported case of lansoprazole-associated LC. Histologic findings from laboratory tests and colon biopsies confirmed diagnoses of LC in both patients in this case report. Patient 1 presented with diarrhea and cramping, which the patient reported had been ongoing for ~3 months, following lansoprazole administration. However, after lansoprazole was discontinued, the symptoms completely resolved within 7 days. Patient 2 presented with diarrhea and cramping, which had been occurring for ~6 months. That patient reported that initial onset commenced ~2 months after a 10-day H pylori eradication combination treatment regimen that included lansoprazole, amoxicillin, and clarithromycin, followed by lansoprazole monotherapy to treat GERD. However, after sulfasalazine (3 g/d) was prescribed for 2 months immediately upon diagnosis of LC, there was little improvement in the effort to control the diarrhea in this patient. After omeprazole 20 mg/d was substituted for lansoprazole, the patient's diarrhea ceased. Follow-up sigmoidoscopy 2 months later revealed normal mucosa and complete normalization of histologic findings. The patient remains diarrhea-free while on omeprazole. A causality assessment using the Naranjo adverse reaction algorithm produced scores of 6 for both patients, suggesting that LC was probably associated with lansoprazole treatment.
  
  
  CONCLUSIONS
  Here we report 2 cases of LC in patients probably associated with the administration of lansoprazole treatment. Complete remission occurred after lansoprazole was discontinued.
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, Gazi University Hospital, Ankara, Turkey ; Department of Pathology, Faculty of Medicine, Gazi University Hospital, Ankara, Turkey.
authors.forename: Zahide
authors.initials: Z
authors.lastname: Simsek
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, Gazi University Hospital, Ankara, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Alagozlu
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, Gazi University Hospital, Ankara, Turkey.
authors.forename: Candan
authors.initials: C
authors.lastname: Tuncer
authors.affiliation: Department of Pathology, Faculty of Medicine, Gazi University Hospital, Ankara, Turkey.
authors.forename: Ayse
authors.initials: A
authors.lastname: Dursun
keywords: gastroesophageal reflux disease; lansoprazole; microscopic colitis