IgG4-related disease (IgG4RD) may initially present with pulmonary pseudotumor, making the diagnosis challenging particularly in patients prone to granulomatous inflammation. Here, we describe the first case of chronic granulomatous disease (CGD) with associated IgG4RD.
An 8.5-year-old male was hospitalized two years ago with exertional dyspnea, mild cough, chest pain, and nocturnal sweating and was found to have a tumor-like mass in the right lung. The histopathologic findings were consistent with non-necrotizing granulomatous inflammation, central neutrophilic micro-abscess, and extensive peripheral fibrosis without any evidence for acid-fast bacilli or fungal elements. Treatment with prednisolone resulted in considerable symptom resolution. After 15 months, following the discontinuation of prednisolone by the patient, symptoms recurred, gradually exacerbated, and he developed anorexia and weight loss. The next chest spiral computed tomography (CT) scan showed a larger mass in the right lung, right lung collapse, and mediastinal metastasis. The abdominal ultrasound and CT scan were normal. In laboratory evaluation, low counts of B and T cells, normal natural killer (NK) cells, high levels of IgG4, and high inflammatory markers were detected. The nitro blue tetrazolium (NBT) test was zero in two consecutive evaluations. In virtue of high IgG4 level, the immunostaining of lung specimen was performed which was inconclusive for IgG4+cells, and staining for CD138 was not available. He was diagnosed with concurrent CGD and IgG4RD, but progressed to respiratory failure and died despite the reinstitution of steroid therapy.
The overlap between inborn errors of immunity (IEIs) and IgG4RD is not common. Further studies to investigate IgG subsets among IEI patients can help elucidate clinicopathological correlations between these two immune-mediated disorders.