Analysis of 8 Cases of Blau Syndrome/Early-onset Sarcoidosis——Clinical Manifestations, Histopathology Features and Gene Mutation Diversity / 罕见病研究

  Objective  To summarize the clinical manifestations, pathological features and gene mutation diversity of Blau syndrome/early-onset sarcoidosis.  Methods  We collected general data, clinical manifestations, and auxiliary examination results from 8 patients who were diagnosed of Blau syndrome/early-onset sarcoidosis and treated in our hospital from January 2011 to December 2022, and then summarized and analyzed their characteristics and diversity.  Results  Among the 8 patients, 4 were males and 4 were females. The onset age was 3 to 8 months old. Rash was the first symptom in 7 patients(87.5%). 6 patients(75.0%) had papules and erythema.3 cases(37.5%) had arthritis. 2 cases(25.0%) had uveitis and other eye inflammation. 4 cases (50.0%) also showed intermittent fever. 3 cases (37.5%) showed symptoms in nerve and respiratory system, and hypertension respectively. The skin histopathology of 8 patients showed non-caseous granuloma formation. In laboratory detection, CRP and TNF-α were significantly increased before treatment, while IL-6, IL-8, TNF-α and IL-2 receptor(IL-2R) were significantly decreased in 5 patients after glucocorticoid therapy. The results of genetic testing showed that 4 of the 7 patients had p.R334W(c.1000C > T) mutation, 1 had p.H313R(c.938A > G) and p.R471C(c.1411C > T)double mutation, and 1 had p.476_477del (c.1427_1429delcct).  Conclusions  Blau syndrome/early-onset sarcoidosis has significant features in clinical manifestations, histopathology and gene mutation, but it also has diversity.

A familial case of Blau syndrome caused by a novel NOD2 genetic mutation / 소아과

Blau syndrome (BS) is a rare autosomal dominant, inflammatory syndrome that is characterized by the clinical triad of granulomatous dermatitis, symmetric arthritis, and recurrent uveitis. Mutations in the nucleotide oligomerization domain 2 (NOD2) gene are responsible for causing BS. To date, up to 30 Blau-associated genetic mutations have been identified within this gene. We report a novel NOD2 genetic mutation that causes BS. A girl, aged 8 years, and her brother, aged 10 years, developed erythematous skin rashes and uveitis. The computed tomography angiogram of the younger sister showed features of midaortic dysplastic syndrome. The brother had more prominent joint involvement than the sister. Their father (38 years) was also affected by uveitis; however, only minimal skin involvement was observed in his case. The paternal aunt (39 years) and her daughter (13 years) were previously diagnosed with sarcoidosis. Mutational analysis revealed a novel c.1439 A>G mutation in the NOD2 gene in both siblings. The novel c.1439 A>G mutation in the NOD2 gene was found in a familial case of BS. Although BS is rare, it should always be considered in patients presenting with sarcoidosis-like features at a young age. Early diagnosis of BS and prompt multisystem workup including the eyes and joints can improve the patient's outcome.

A Case of Early Onset Sarcoidosis Masquerading as Juvenile Rheumatoid Arthritis / 대한피부과학회지

Sarcoidosis is a chronic multisystemic granulomatous disorder of unknown cause that occurs rarely in children. There are 2 types of sarcoidosis in children: early onset in children less than 4 years old and late onset in children 8 to 15 years old. The clinical manifestation of late onset sarcoidosis in children is similar to that of adults. Early onset sarcoidosis is difficult to diagnose however because its symptoms mimic those of juvenile rheumatoid arthritis (JRA). Early differentiation of sarcoidosis from JRA is important in planning treatment strategies and in counseling patients and families. Here we present a case of early onset sarcoidosis resembling JRA.