Telepathology a Useful Method in the Diagnosis Digestive Biopsies with Rare Entities. Case Presentation of a Collagenous Gastritis.

Abstract

Introduction/ Background
Collagenous gastritis is a rare entity in current surgical pathology practice. Since the introduction of the term until present, only small series and isolated cases have been reported, generally by high-specialized centers in gastrointestinal pathology. In current practice, the diagnosis of this unusual affection is based on clinical data corroborated with endoscopic and pathological findings. Due to the small number of cases the diagnostic criteria are partly taken from microscopic colitis diagnosis. Thus, it is considered that the association of the appropriate clinical context (stomach pain, watery diarrhea, endoscopic nodular appearance) and histological gastritis changes with collagen deposition of dense material with a 10um minimum variable thickness that comprises capillaries and inflammatory elements. The technical advantage of a digital slide scanner is allowing access to an experienced pathologist in digestive pathology’s opinion and conducting precision measurement.

Aims
Our presentation brings to attention of pathologist community a rarely diagnosed entity and the advantages of tele-pathology in timely accessing an expert opinion and performing accurate measurements.

Methods
We received gastric biopsy samples endoscopically taken from a 56-year female who complained of transit disorders, vomiting, epigastric pain that did not improve after IPP treatment. On endoscopy exam a nonspecific aspect with discrete erythema and vaguely nodular appearance of the gastric mucosae was noted. The specimens were paraffin embedded, and serial sections were stained HE, AB-PAS and MGG. The obtained slides were fully scanned and a gastrointestinal pathology expert advice was requested. Subsequently, a Mason’s Trichrome stain and tenascin immunohistochemistry test were performed. The examined section showed gastric mucosal epithelium with scarce intraepithelial lymphocytes (5-6 lymphocytes/100 cells). The surface epithelium had the tendency to roll away from the variable thickened stroma. The glandular architecture and chorion were modified by a nonspecific inflammatory infiltrate. A diagnose of chronic inactive gastritis with intestinal metaplasia areas was propose, and an expert opinion was requested. Digitally scanned sections using the Leica II Aperio slide scanner were taken. Examination of slides was made using the Imagescope12.2 Leica. Micrometeric measurements of the hyaline material varied between 9.5-51um. The review of glass slides on traditional optical microscope was made confirming the diagnosis.

Results
Collagenous gastritis remains an underestimated condition due to its low incidence and lack of expertise in the field. Hence telepathology becomes a useful tool for requesting a second opinion and precisions
measurements.