Table 3.
Differential Diagnosis of Granulomatous Inflammation in Lymph Nodes [50]
| Necrotizing/Suppurative Granulomas | Clinical | Nodal Sites | Histological Features1 | Histochemical stains & Immunohistochemistry | Other Investigations |
|---|---|---|---|---|---|
| Mycobacterial lymphadenitis (Mycobacterium tuberculosis) [153, 154] | History of exposure to TB | Cervical, axillary, mediastinal | Central necrosis. Acid fast bacilli |
Ziehl-Neelson: + Fite: + |
Tuberculin skin test IFN-γ release assay PCR/culture |
| Histoplasmosis (Histoplasma capsulatum) [156, 157] | Asymptomatic, pulmonary infection or disseminated depending on immune status and exposure level | Hilar or others in disseminated | 2–4μm, clustered in macrophages. Difficult to appreciate in granulomas without histochemical stains |
GMS: + PAS: + Mucicarmine: − |
Serology Histoplasma antigen EIA Culture |
| Cryptococcosis (Cryptococcus neoformans, Cryptococcus gattii) [156, 202, 203] | Pulmonary involvement. May involve CNS. May be disseminated |
Cervical, hilar, axillary, inguinal and others | Well-formed granulomas. May form cystic spaces with gelatinous material. 5–10μm - within clear spaces in granulomas and macrophages | PAS: + GMS: + Mucicarmine: + Fontana-Masson: + |
Cryptococcal antigen EIA Culture |
| Cat Scratch disease (Bartonella henslae) [158, 159, 162, 163] | History of contact with cats Skin lesion |
Axillary, cervical, epitrochlear | Warthin-Starry: Pleomorphic coccoid or curved bacilli in clumps or singly in vessel walls or in foci of necrosis | Brown-Hopps: Faint (gram- negative) Warthin-Starry: + Ziehl-Neelson: − Immunohistochemistry for Bartonella henslae |
Serology PCR |
| Lymphogranuloma venereum (Chlamydia trachomatis, L1, L2, L3) [164, 204] | Mucosal or skin lesions in genital tract or rectum | Inguinal, femoral or iliac nodes. May fistulate. | Macrophages with vacuoles. Organisms form a central clump or a peripheral rim in vacuoles | Warthin-Starry: + PAS: − Ziehl-Neelson: − Brown-Hopps: Gram- negative |
Serology Nucleic acid detection |
| 1. H&E. Features on special stain if indicated | |||||
| Non-Necrotizing Granulomas | Clinical | Nodal Sites | Histological Features | Histochemical stains & Immunohistochemistry | Other Investigations |
| Sarcoidosis [142, 144, 148] | Multi-system disease; pulmonary symptoms; erythema nodosum | Bi-hilar adenopathy | Sharply demarcated granulomas; Asteroid bodies, Schaumann bodies; Hamazaki- Wesenberg bodies | Ziehl-Neelson and fungal stains are negative. Hamazaki-Wesenberg bodies are GMS + and PAS + (Pitfall) |
Serum ACE levels Chest x-ray Microbiological cultures |