A case of IgG4-related sclerosing disease with retroperitoneal fibrosis, autoimmune pancreatitis and bilateral focal nephritis

IgG4-Related Diseases Involving Bilateral Renal Pelvises Successfully Treated with Steroid Therapy

Immunoglobulin (Ig) G4-related diseases are very rare diseases and are difficult to diagnose and treat. Here, we report a rare condition, an IgG4-related disease involving the bilateral renal pelvises, which was successfully treated with steroid therapy. A 64-year-old female was admitted with left flank pain and hematuria. Computed tomographic images showed irregular enhancing masses around the bilateral renal pelvises and lymph nodes in the left para-aortic area. A histopathological examination of a renal needle biopsy revealed numerous cells that were positive for IgG and more than 10 IgG4-positive cells per high-powered field. The IgG4/IgG ratio was more than 40%. Her serum IgG4 level was elevated to 1440 mg/dL, and her IgG4/IgG ratio was 82.1%. After a diagnosis of IgG4 sclerosing disease, a double-J ureteral stent was inserted and steroid therapy was performed for 20 weeks. Her symptoms dramatically improved, and the follow-up images showed a resolved state. There was no relapse of the disease for more than 6 months after the removal of the stent.

Autoimmune Disease Classification Based on PubMed Text Mining

Autoimmune diseases (AIDs) are often co-associated, and about 25% of patients with one AID tend to develop other comorbid AIDs. Here, we employ the power of datamining to predict the comorbidity of AIDs based on their normalized co-citation in PubMed. First, we validate our technique in a test dataset using earlier-reported comorbidities of seven knowns AIDs. Notably, the prediction correlates well with comorbidity (R = 0.91) and validates our methodology. Then, we predict the association of 100 AIDs and classify them using principal component analysis. Our results are helpful in classifying AIDs into one of the following systems: (1) gastrointestinal, (2) neuronal, (3) eye, (4) cutaneous, (5) musculoskeletal, (6) kidneys and lungs, (7) cardiovascular, (8) hematopoietic, (9) endocrine, and (10) multiple. Our classification agrees with experimentally based taxonomy and ranks AID according to affected systems and gender. Some AIDs are unclassified and do not associate well with other AIDs. Interestingly, Alzheimer's disease correlates well with other AIDs such as multiple sclerosis. Finally, our results generate a network classification of autoimmune diseases based on PubMed text mining and help map this medical universe. Our results are expected to assist healthcare workers in diagnosing comorbidity in patients with an autoimmune disease, and to help researchers in identifying common genetic, environmental, and autoimmune mechanisms.

Immunoglobulin g4-related systemic sclerosing disease: a case involving the ureter and kidney

Immunoglobulin (Ig) G4-related sclerosing disease is a newly defined clinicopathological entity characterized by lymphoplasmacytic infiltration of IgG4-positive plasma cells and varying degrees of fibrosis within affected tissues. Patients usually exhibit multisystem involvement and often respond well to steroid and immunosuppressive therapy. This report presents a case of IgG4-related sclerosing disease involving the ureter and kidney. We hope to bring IgG4-related sclerosing disease to the attention of urologists, because it is an uncommon disease that commonly responds to systemic corticosteroids.

Efficacy of laparoendoscopic single-site biopsy for diagnosis of retroperitoneal tumor of unknown origin

BACKGROUND AND PURPOSE

When percutaneous image-guided biopsies are not possible for retroperitoneal tumor of unknown origin (RTUO), surgical tissue diagnosis becomes necessary. Laparotomy and laparoscopic surgery are current standard treatments; however, the laparoendoscopic single-site (LESS) approach offers many potential benefits. We describe our technique for LESS biopsy of RTUO.

PATIENTS AND METHODS

Five patients underwent LESS biopsy for diagnosis of RTUO. A multichannel port was inserted into the peritoneal or retroperitoneal space through a 3-cm skin incision, which adequately exposed the retroperitoneal tumor. The specimen was grasped and isolated circumferentially from the surrounding tissue.

RESULTS

LESS surgery was performed successfully without any complications such as open conversion. Mean operative time was 183 min and estimated blood loss was negligible. The diagnoses were IgG4-related retroperitoneal fibrosis (n = 4) and lymphoma (n = 1). Sufficient specimens were safely obtained not only for pathological diagnosis but also for further examinations such as immunophenotyping or DNA analysis. Convalescence was satisfactory. All patients were treated appropriately according to the resulting diagnosis.

CONCLUSIONS

LESS biopsy for RTUO is a safe and effective alternative to open surgical and standard laparoscopic biopsies. Further studies of clinical experiences are needed to confirm the benefits of this new technique.

Peripheral T-cell lymphoma that developed during the follow-up of IgG4-related disease

IgG4-related disease is a recently recognized fibroinflammatory disorder characterized by extensive IgG4-positive plasma cell and lymphocyte infiltration of various organs. The pancreatic manifestation of IgG4-related disease is called autoimmune pancreatitis (AIP), in which autoimmune mechanisms are likely involved. On the other hand, some autoimmune and chronic inflammatory disorders, such as Sjögren's syndrome and rheumatoid arthritis, are associated with increased risks of non-Hodgkin lymphoma (NHL). There have been a few reports of cases with IgG4-related disease that had subsequently developed NHL, however, all of them suffered from B-cell lymphoma. We describe the first case of NHL, compatible with a subtype of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), which arose in IgG4-related sclerosing cholangitis. As patients with IgG4-related disease may be at an increased risk of developing NHL, such presentation during the follow-up of IgG4-related disease should be carefully scrutinized to exclude NHL.