Department of Paediatrics, First Faculty of Medicine, Charles University in Prague, Thomayer University Hospital, Prague, Czech Republic
National Institute of Child Tuberculosis and Respiratory Diseases, Dolny Smokovec, Slovakia
Eur J Dermatol. 2022 Sep 7;32(4):495-504. doi: 10.1684/ejd.2022.4281.
Inborn errors of IL-12/IL-23-IFNγ immunity underlie Mendelian susceptibility to mycobacterial diseases (MSMD), a group of immunodeficiencies characterized by a highly selective susceptibility to weakly virulent strains of mycobacteria, such as non-tuberculous mycobacteria (NTM) and bacillus Calmette-Guérin (BCG). Cutaneous mycobacterial infections are common in MSMD and may represent a red flag for this immunodeficiency.
We present a case series of four paediatric patients with MSMD, specifically with IFNγR1 and STAT1 deficiencies, and cutaneous NTM/BCG infections to increase awareness of this immunodeficiency, which may, in some cases, be intercepted by the dermatologist and thus timely referred to the immunologist.
MATERIALS & METHODS: Clinical, laboratory and genetic investigations of the four paediatric patients with MSMD are presented.
All four presented patients experienced early complications after BCG vaccination. Two patients suffered recurrent mycobacteriosis, one patient experienced delayed BCG reactivation, and one patient died of disseminated avian mycobacteriosis. The dermatological manifestation in these patients included destructive nasal ulcerations, scrofuloderma of various sites and lupus vulgaris. All patients had a normal basic immune phenotype.
The presented cases demonstrate that NTM/BCG infections in otherwise seemingly immunocompetent patients should raise suspicion of MSMD. This is of utmost importance as specific therapeutic approaches, such as IFNγ treatment or haematopoietic stem cell transplantation, may be employed to improve the disease outcome.
IL-12/IL-23-IFNγ 免疫的先天缺陷是分枝杆菌病（MSMD）易感性的基础，这是一组免疫缺陷病，其特征是对分枝杆菌（如非结核分枝杆菌（NTM）和卡介苗（BCG））的弱毒菌株具有高度选择性易感性。皮肤分枝杆菌感染在 MSMD 中很常见，可能是这种免疫缺陷的一个警示信号。
我们报告了四例 MSMD 患儿的病例系列，特别是 IFNγR1 和 STAT1 缺陷的病例，以及皮肤 NTM/BCG 感染，以提高对这种免疫缺陷的认识，在某些情况下，皮肤科医生可能会发现这种免疫缺陷，并及时转介给免疫学家。
对四例 MSMD 患儿的临床、实验室和遗传学进行了调查。
所有四名患者在接种 BCG 后均出现早期并发症。两名患者患有复发性分枝杆菌病，一名患者出现 BCG 再激活延迟，一名患者死于播散性禽分枝杆菌病。这些患者的皮肤表现包括破坏性鼻溃疡、各种部位的寒性脓肿和狼疮样溃疡。所有患者的基础免疫表型均正常。
所报告的病例表明，在看似免疫功能正常的患者中出现 NTM/BCG 感染应怀疑 MSMD。这一点非常重要，因为可以采用特定的治疗方法，如 IFNγ 治疗或造血干细胞移植，来改善疾病结局。
