Bronchoalveolar lavage cytology resembles sarcoidosis in a subgroup of granulomatous CVID

signs and bronchiectasis predominated in CVID.In line with their findings, in our cohort with proven granulomatous disease, the majority of HRCTs demonstrated macronodular lung involvement (eight out of 11 patients).The two patients with micronodular involvement showed a randomly distributed pattern, which also differs to the characteristic perilymphatic distribution in sarcoidosis, as already shown by BOUVRY et al. [1].Moreover, some patients presented with predominant coarse reticular lines or groundglass lesions.It is intriguing to speculate whether the difference in CD4/CD8 ratio reflects different forms or stages of pulmonary inflammation in CVID, which may correlate to certain computed tomography morphology.This has been previously described in sarcoidosis, where lower CD4/CD8 ratios and increased neutrophils correlated with progressive, fibrotic disease and the need for steroid treatment [3][4][5].In our small CVID cohort, lung function and computed tomography findings were mostly stable during follow-up, suggesting that a high CD4/CD8 ratio in granulomatous CVID is associated with a mild and nonprogressive ILD (table 1).Only two patients showed a deterioration of lung function parameters.Interestingly, both of these patients showed rather low CD4/CD8 ratios in comparison to the total study population (2.0 and 3.8).In conclusion, in addition to the report by BOUVRY et al.[1], we found that in a subgroup of CVID patients with histologically confirmed granuloma formation, BAL cytology resembles sarcoidosis.All patients presented with high BAL lymphocytosis, high CD4/CD8 ratio and the majority with nodular lung disease on computed tomography.Thus, differences in BAL cytology and computed tomography morphology most likely reflect heterogeneity in CVID-associated granulomatous and interstitial lung disease.Our preliminary data suggest a rather favourable prognosis of ILD in this subgroup of CVID with high CD4/CD8 ratio in the BAL.Some of these findings may potentially guide management and predict outcome of these patients, but larger studies are needed to determine diagnostic and prognostic value of specific markers during detailed characterisation of interstitial lung disease in this heterogeneous disease.