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Differential diagnosis of primary immunodeficiency in patients with BCGitis and BCGosis: A single-centre study
Elif Soyak Aytekin1, Armagan Keskin2, Cagman Tan3
1Divisions of Pediatric Immunology, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey.
Insights
BCG infections are common in patients with primary immunodeficiency disease (PIDD). This study found PIDD in over half of BCG-infected patients, particularly those with BCGosis, highlighting the need for caution in BCG vaccination for at-risk individuals.
Area of Science:
- Immunology
- Infectious Diseases
- Genetics
Background:
- BCG infections are a known complication in individuals with primary immunodeficiency diseases (PIDD).
- Understanding the prevalence of PIDD in patients experiencing BCG infections is crucial for risk assessment and management.
Purpose of the Study:
- To determine the proportion of patients with BCG infections who have an underlying PIDD.
- To identify specific types of PIDD associated with BCG infections and their clinical manifestations.
Main Methods:
- Retrospective analysis of 47 patients diagnosed with BCGitis or BCGosis between 2015 and 2020.
- Evaluation of PIDD diagnosis, affected organs, specific immunodeficiency types, clinical features, and mortality.
Main Results:
- 55.3% of patients with BCG infections had an underlying PIDD.
- PIDD was present in 92.3% of BCGosis cases and 41.2% of BCGitis cases.
- Common PIDDs included Mendelian susceptibility to Mycobacterial disease (MSMD), predominantly antibody deficiency (PAD), and severe combined immunodeficiency (SCID). Parental consanguinity, lymphadenopathy, and hepatomegaly were frequent in PIDD patients.
Conclusions:
- A significant proportion of patients with BCG infections, especially BCGosis, harbor underlying primary immunodeficiency diseases.
- Clinical features like parental consanguinity and lymphadenopathy can suggest PIDD in BCG-infected patients.
- BCG vaccination requires careful consideration in individuals suspected of having PIDD.
Abstract:
BCG infections occur more frequently in patients with underlying primary immunodeficiency disease (PIDD). In this study, we aimed to evaluate the ratio of PIDD in the patients with BCG infections. Patients with BCG infections were analyzed in a tertiary referral centre in the 2015-2020 period. Forty-seven patients with BCGitis/BCGosis were evaluated; thirty-four (72.3%) had BCGitis, and 13 (27.7%) had BCGosis. Common tissue and organs affected are lymph nodes (57.4%), skin and subcutaneous tissue (48.9%), lungs (23.4%) and liver (17%). PIDD was shown in 26 patients (55.3%), including 92.3% of patients with BCGosis and 41.2% of patients with BCGitis. Ten patients had Mendelian susceptibility to Mycobacterial disease (MSMD) (21.2%), six had predominantly antibody deficiency (PAD) (12.7%), five had severe combined immunodeficiency (SCID) (10.6%), three had CGD (6.3%), and two had CID (4.2%). Mortality was reported in two patients (4.2%) with CID (ZAP70 deficiency (n = 1) and PIK3R1 deficiency (n = 1)). Parental consanguinity (84%), axillary lymphadenopathy (65%), mycobacterial lung disease (42%), hepatomegaly (30%) and growth retardation (19%) were significantly high in patients with PIDD diagnosis. Isolated vaccination site infection was also recorded in patients with PIDD (CID (n = 1), SCID (n = 1), PAD (n = 5)). BCG vaccination should be planned with caution for the cases with suspected PIDD. This study indicates that almost all patients (92.3%) with BCGosis and one in every two patients (41.2%) with BCGitis have an underlying PIDD. Parental consanguinity, axillary lymphadenopathy, mycobacterial lung disease, hepatomegaly and growth retardation (19%) are important clinical features in the differential diagnosis of PIDD.
