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Immunoglobulin G4 related disease — Clinical Guidelines

Overview

Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibroinflammatory condition characterized by elevated serum IgG4 levels and tissue infiltration by IgG4-positive plasma cells, leading to organ swelling and dysfunction, commonly affecting the pancreas, biliary tree, and salivary glands. 1 2 4

Diagnosis

Comprehensive work-up including histology, imaging (CT, MRI), serology, and assessment of organ involvement.

Elevated serum IgG4 levels and characteristic histopathological features (diffuse lymphoplasmacytic infiltrate with abundant IgG4+ plasma cells).

Imaging often shows tumefactive lesions and organ enlargement; combination of CT and MRI recommended for initial evaluation. 1 4

Management

First-line treatment: Glucocorticoids (prednisone equivalent 0.6-0.8 mg/kg/day, typically starting at 30-40 mg/day) for 1 month to induce remission, followed by gradual tapering over 2 months.

Assessment of response: Evaluate clinical, biochemical, and morphological markers at 2-4 weeks post-initiation.

Maintenance therapy: Consider prolonged glucocorticoid use in multi-organ disease or history of relapse.

Steroid-resistant cases: Novel therapies such as B-cell depleting agents (e.g., rituximab) may be considered. 1 4

Special Populations

Pediatrics: Guidelines cover both adults and children, but specific pediatric management details are not extensively detailed in provided abstracts.

Elderly: No specific recommendations differing from general guidelines; careful monitoring for polypharmacy and drug interactions is advised given increased complexity of care. 5

Key Recommendations

Diagnosis requires comprehensive evaluation including histology, imaging, serology, and response to glucocorticoids. (Evidence: Strong 4)

Initiate glucocorticoid treatment at 0.6-0.8 mg/kg/day, tapering over 2 months post-remission induction. (Evidence: Strong 1 4)

Evaluate treatment response within 2-4 weeks using clinical, biochemical, and imaging markers. (Evidence: Moderate 1)

Consider prolonged glucocorticoid therapy in cases with multi-organ involvement or history of relapse. (Evidence: Expert opinion 1)

Explore B-cell depleting agents for steroid-resistant cases. (Evidence: Moderate 4)

References

1 Vujasinovic M, Lanzillotta M, Culver EL, Rebours V, Drenth JPH, Stojkovic Lalosevic M et al.. Adherence to United European Gastroenterology Guidelines on Diagnosis and Therapy of Immunoglobulin-G4-Related Digestive Disease. United European gastroenterology journal 2025. link 2 Spandorfer R, Ahmad M, Khosroshahi A. Clinical Characteristics and Classification Criteria Performance in a Single-Center Cohort of 114 Patients With Immunoglobulin G4-Related Disease. Journal of clinical rheumatology : practical reports on rheumatic & musculoskeletal diseases 2023. link 3 Kowa JY, Kim TK, Khalili K, Elbanna KY. Patterns of Relapse and Complications of Immunoglobulin G4-Related Disease. Journal of clinical rheumatology : practical reports on rheumatic & musculoskeletal diseases 2023. link 4 Löhr JM, Beuers U, Vujasinovic M, Alvaro D, Frøkjær JB, Buttgereit F et al.. European Guideline on IgG4-related digestive disease - UEG and SGF evidence-based recommendations. United European gastroenterology journal 2020. link 5 Ertuna E, Arun MZ, Ay S, Koçak FÖK, Gökdemir B, İspirli G. Evaluation of pharmacist interventions and commonly used medications in the geriatric ward of a teaching hospital in Turkey: a retrospective study. Clinical interventions in aging 2019. link 6 Bae K, Jung An H, Jeon KN, Hyun Song D, Kim SH, Kim HC. Coexistence of nontuberculous mycobacterium and IgG4-related disease in a solitary pulmonary nodule: A case report. Medicine 2019. link 7 Katabathina VS, Khalil S, Shin S, Lath N, Menias CO, Prasad SR. Immunoglobulin G4-Related Disease: Recent Advances in Pathogenesis and Imaging Findings. Radiologic clinics of North America 2016. link 8 Lowe GC, Bogner RR, el-Azhary RA, Gonzalez-Santiago TM, Kindle SA, Lehman JS et al.. Cutaneous manifestations of immunoglobulin G4-related disease: what dermatologists need to know. International journal of dermatology 2015. link 9 Asai S, Okami K, Nakamura N, Shiraishi S, Sugimoto R, Anar D et al.. Localized or diffuse lesions of the submandibular glands in immunoglobulin g4-related disease in association with differential organ involvement. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine 2013. link 10 Hazen-Martin DJ, Simson JA. Immunocytochemical localization of nerve growth factor: effects of fixation. The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society 1984. link

Immunoglobulin G4 related disease