Abbott JK, Gelfend EW. atypical cases with unexplained chronic signs such as fever of unknown origin (even in older patients) after tuberculosis, HIV, neoplasia and connective tissue disease have been ruled out. Common causes of hypogammaglobulinaemia should be excluded before CVID is considered. CVID can mimic sarcoidosis. strong class=”kwd-title” Keywords: Common variable immunodeficiency, granulomatosis, aged CASE PRESENTATION Common variable immunodeficiency (CVID) is the most frequent primary immunodeficiency. It is characterized by low levels of immunoglobulins IgG, IgA and sometimes IgM, which result in recurrent and severe infections, associated in some cases with autoimmune manifestations and granulomatous lesions[1,2]. The fact that it is rarely considered as a diagnosis in adults can lead to diagnostic delay, especially in older patients. The case presented here is interesting because of its late onset. It is important for practitioners to remember that a diagnosis of primary immunodeficiency is still possible in older patients, especially those with atypical clinical features that remain unexplained after routine work-up. A 63-year-old woman presented with prolonged fever and poor physical condition for several months. Her personal history was unremarkable, but her husband had been treated for pulmonary tuberculosis 7 years previously. She had a family history of systemic lupus in her sister, autoimmune hypothyroidism in her brother and Graves disease in her daughter. Fever and weight loss were associated with liquid diarrhoea and a chronic dry cough. The patient was first admitted to the infections department, where she was investigated for HIV, tuberculosis (TB) and malignancy. Results showed anaemia (haemoglobin 10 g/dl), lymphopenia, inflammatory syndrome (ESR STAT3-IN-1 73 mm, CRP 68 mg/l), a negative uvomorulin tuberculin skin test, unfavorable HIV serology, and unfavorable blood and stool cultures. A CT scan (Fig. 1) showed micronodular and interstitial infiltrates associated with bronchiectasis, which can indicate TB. Three sputum smears were unfavorable for TB. Because of the digestive system involvement, a gastro-intestinal endoscopy was performed and showed nodular gastritis and colitis and isolated giardiasis, which was treated with metronidazole with a good response. Open in a separate window Physique 1 Chest radiograph showing micronodular and interstitial infiltrates in both lungs The patient was discharged with a prescription for anti-TB drugs which she took for 9 months without any bacteriological or histological evidence of TB. However, the clinical course was marked by the occurrence of diffuse arthritis and lymphadenopathy and previous clinical and radiological indicators persisted. Consequently, as systemic disease was suspected, the patient was admitted to the internal medicine department for investigation. Immunological parameters (antinuclear antibody, rheumatoid factor, ACPA, ANCA, Coombs) and kidney investigations were unfavorable. A STAT3-IN-1 lymph node biopsy showed the presence of non-necrotizing granuloma (Fig. 2). New ocular symptoms were diagnosed as STAT3-IN-1 granulomatous uveitis. Open STAT3-IN-1 in a separate window Physique 2 Node biopsy showing non-necrotizing granuloma There was a strong suspicion of sarcoidosis because of the pulmonary involvement, the ocular and joint manifestations, the presence of granulomatous disease in the biopsy and the non-response to anti-TB drugs. The work-up showed normal angiotensin converting enzyme and calcium and phosphorus levels. Lymphoma was also a possible diagnosis but an immunohistochemistry study performed on the lymph node biopsy was negative as was a bone marrow biopsy. Protein electrophoresis showed hypogammaglobulinaemia (Fig. 3). Open in a separate window Figure 3 Protein electrophoresis showing hypogammaglobulinaemia Further investigations revealed decreased serum immunoglobulin levels: IgG 1.1, IgA 0.3 and IgM 0.4. A flow cytometric study of lymphocyte subpopulations showed a low CD19 count (2%) with a normal range of T lymphocytes. These findings suggested a primary immunodeficiency, in particular CVID. In light of these results, a CVID with granulomatous manifestations was diagnosed based on European Society for Immunodeficiencies (ESID) criteria (Table 1). Our patient was treated with immunoglobulin perfusions, oral corticosteroids (especially for the ocular involvement), respiratory physiotherapy and azithromycin for bronchiectasis. Evolution was good: the fever resolved, respiratory symptoms have improved, and our patient has gained weight and recovered her vision. Table 1 European Society for Immunodeficiencies (ESID) 2014 criteria for common variable immunodeficiency (CVID)[3] At least one of the following: Increased susceptibility to infection Autoimmune manifestations Granulomatous disease Unexplained polyclonal lymphoproliferation Affected family member with antibody deficiency AND A marked decrease in IgG and marked decrease in IgA with or.