RESUMEN
Immunoglobulin G4 sclerosing cholangitis (IgG4-SC), firstly described in 2004, is the biliary manifestation of a recently described multisystem immune-mediated disease known as IgG4-related disease. IgG4-SC is a unique and rare type of cholangitis of unknown etiology and its precise prevalence rate is still unclear. It is characterized by bile duct wall thickening and high levels of systemic serum IgG4 plasma cells. Differential diagnoses for IgG4-SC include benign (primary sclerosing cholangitis) as well as malignant (extra-hepatic cholangiocarcinoma) diseases. Discrimination between these entities is very important, due to the fact that they have different biological behaviors and different therapeutic strategies. The rare IgG4-SC subgroup with its puzzling manifestations carries a hefty diagnostic challenge for the treating physicians, and inaccurate diagnosis can lead to unnecessary morbid surgical procedures. With the paucity and relative weakness of available data in the current literature, one needs to carefully review all available parameters. A low threshold of suspicion is required to try and prevent missing IgG4-SC. IgG4-SC is highly responsive to steroid treatment, especially during the early inflammatory phase, while delay in management could lead to fibrosis and organ dysfunction. On the other hand, cholangiocarcinoma is treated by means of surgery and/or chemotherapeutic agents.
RESUMEN
BACKGROUND/AIMS: Nuclear medicine scintigraphies have been reported to assist in making the diagnosis of inflammatory bowel disease. This work aimed to assess the role of radiolabeled leukocyte scintigraphy for the diagnosis of suspected inflammatory bowel disease. METHODOLOGY: Forty-six adult patients were referred for labeled leukocyte scintigraphy for the evaluation of active abdominal pain. The patient population included inpatients and outpatients, with known or suspected inflammatory bowel disease. The nuclear medicine staff was blinded to the patient's specific complaints. RESULTS: The labeled leukocyte scintigraphy was positive in 11 of the 15 patients eventually determined to have Crohn's disease. Four of the 15 were false negatives. All four of the ulcerative colitis patients had normal scans. There were no false-positive scans. The positive predictive value was thus 100%, the negative predictive value was 77%, and the sensitivity and specificity were 58% and 100% respectively for Crohn's disease. CONCLUSIONS: We found radiolabeled leukocyte scintigraphy helpful in prospective, blinded assessments of patients with non-stricturizing or non-fistulizing forms of Crohn's disease. Scintigraphy may be more justified for reassessments rather than in making an initial diagnosis. The scans were of value in Crohn's disease but not for ulcerative colitis.