A 33-year-old multiparous woman was referred to the Rheumatology unit at Baghdad teaching hospital as a consultation case from breast clinic. The condition started with two- month’s history of a palpable painful mass in the left breast that increased in size gradually with no overlying skin changes. She attended the breast clinic for evaluation, breast ultrasound revealed mastitis for which multiple courses of antibiotics has been prescribed without improvement. A week later she developed multiple tender red nodules on the lower extremities with both ankle joints swelling and a low grade fever (Fig. 1), several types of analgesia and low dose prednisolone was started by her physician with no benefit. Past medical history was insignificant. There was no history of recent parturition, breastfeeding, or oral contraceptive pills use in the past three years.
An informed consent was obtained from the patient.
On examining the patient at time of presentation, a tender mass was noted (3x2 cm) in upper lateral quadrant of the left breast that was firm mobile with smooth surface and normal overlying skin. Two lymph nodes at left axillary region were palpable. Multiple erythematous tender nodules were observed on the extensor surface on both legs consistent with Erythema Nodosum (EN). Patient had obvious arthritis of both ankles. Vital signs examination was normal. Acute phase reactants were elevated [erythrocyte sedimentation rate: 70 mm/hour (normal, 0–20), C-reactive protein levels: 15 mg/L (normal, 0–3)]. Leukocyte count was normal as well as the rest of biochemistry blood tests.
Tuberculin skin test (TST) was anergic (0 mm). IGRA test was also negative. Extra pulmonary tuberculosis of breast was excluded with negative tuberculosis gene expert study of the aspirated fluid (repeated twice), and negative acid fast bacilli staining from aspiration material of the lesion. Chest X ray was normal. Angiotensin converting enzyme (ACE) as well as serum calcium level was within the normal range. Sarcoidosis and tuberculosis were excluded with these findings. Bacterial and fungal cultures were negative. Autoimmune markers (antinuclear antibody, extractable nuclear antibodies and anti-neutrophil cytoplasmic antibody) were negative using immunofluorescence method, rheumatoid factor and anticitrullinated antibody level was within normal range. Serum IGG4 level was normal.
Upon repeating Ultrasound examination, mastitis with granuloma was seen in the left breast. Diagnostic fine needle aspiration (FNA) was performed. Cytological examination was nonspecific with granulomatous inflammation consisting of neutrophils, lymphocytes, and multinucleated histiocytic giant cells.
An excisional biopsy was performed with the results demonstrating numerous non necrotizing granulomas with multinucleated giant cells with no significant atypia, malignancy or fibrosis. Through biopsy and exclusion of other possible diseases leading to granulomatous inflammation mentioned above, patient was diagnosed as IGM accompanied by EN and reactive arthritis.
Initial treatment was meloxicam 7.5 mg daily, prednisolone 20 mg daily, azathioprine Table 50 mg twice daily and colchicine Table 0.5 mg per day. On follow-up EN and arthritis regressed completely. Patient was free of symptoms through the duration of follow up.