Association of the toll-like receptor 9 gene polymorphisms with Behcet's disease in a Japanese population

Toll-like receptor 9 (TLR9) genetic variants rs187084 and rs352140 confer protection from Behcet's disease among Iranians

BACKGROUND

Behcet's disease (BD) is a multisystem and multifactorial autoimmune disease characterized by relapsing episodes of oral aphthae, genital ulcers, and ocular and skin lesions. Toll-like receptor 9 (TLR9) has pro-inflammatory roles and its genetic variants might be involved in the pathogenesis of inflammatory diseases.  METHODS: Two hundred five BD patients and 207 age and sex-matched healthy controls were evaluated for TLR9 single nucleotide polymorphisms - 1486 T/C (rs187084) and + 2848:G/A (rs352140) using polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR).

RESULTS

Healthy individuals had a significantly higher frequency of rs187084 AG and AG + GG genotypes than BD patients (p = 0.02 and p = 0.018; respectively). Of interest, healthy males had a significantly higher frequency of rs187084 AG + GG genotype and G allele than male BD patients (p = 0.035 and p = 0.045; respectively). However, rs187084 AG genotype and G allele frequencies were significantly higher in male patients with genital aphthous (p = 0.01 and p = 0.046; respectively). Furthermore, a significantly higher frequency of rs352140 CT and TT + CT genotypes was detected in healthy individuals than in BD patients (p = 0.01, and p = 0.032; respectively). Such results were also seen in healthy females than female patients (p = 0.001, and p = 0.004; respectively). Haplotype analysis revealed a significantly higher frequency of A-C and G-C haplotypes among patients and healthy subjects, respectively (p = 0.002 and p = 0.000; respectively).

CONCLUSION

Our data suggested that rs187084 AG and AG + GG genotypes and rs352140 CT and TT + CT genotypes protect Iranian individuals from BD but rs187084 AG genotype and G allele predispose male BD individuals to genital aphthous. However, additional studies are required to verify these results.

Secondary cutaneous aspergillosis in a child with Behçet’s disease: a case-based update

Background

Invasive aspergillosis (IA) is one of the rarest opportunistic fungal infections and has increased in frequency worldwide in recent years. It is a life-threatening infection associated with high mortality rates. Invasive pulmonary aspergillosis (IPA) is the most severe form of the disease. Extrapulmonary forms can develop as a primary infection or occur as part of a disseminated infection from the lung in severely immunocompromised patients. The major limitation in the management of these infections is the challenge of early diagnosis.

Case presentation

Here we report a case of secondary cutaneous aspergillosis that developed from extensive pulmonary aspergillosis in a 3-year-old female who underwent immunosuppressive therapy for a diagnosed Behçet disease (BD). Aspergillus hyphae were identified on skin biopsies. Cultures grew Aspergillus fumigatus. The diagnosis of cutaneous aspergillosis enabled us to diagnose IPA, although there was no mycopathological proof of lung infection. The patient was successfully treated with voriconazole (8 mg/kg/day) and surgical debridement of the skin lesion.

Conclusions

Although cutaneous involvement in aspergillosis is extremely uncommon, it may be the presenting feature in some cases, allowing for an accurate and timely diagnosis of deeply infected sites. Accordingly, when evaluating skin lesions in immunocompromised individuals, especially debilitated children with underlying diseases requiring long-term immunosuppressive agents, cutaneous aspergillosis should be vigilantly considered.

SIMILARITIES AND DIFFERENCES BETWEEN FAMILIAL MEDITERRANEAN FEVER AND BEHÇET’S DISEASE

Familial Mediterranean Fever (FMF) is the most common monogenic autoinflammatory disease, mainly affecting populations originating from the Eastern Mediterranean region. Behçet’s Disease (BD) is grouped in polygenic autoinflammatory diseases. It is a systemic vasculitis that affects all types and sizes of blood vessels. The aim of this article is to shed light on similarities and differences between FMF and BD. BD is frequently reported along the ancient Silk Road, extending from the Far East to the Mediterranean basin. Several studies have searched for the association between FMF and BD. FMF is caused by mutations of the MEditerranean FeVer (MEFV) gene while an increased frequency of MEFV mutations is reported in BD patients. Although BD and FMF share some epidemiological and pathophysiological features, there are distinct clinical characteristics of these nosological entities. Mucocutaneous manifestations, especially recurrent oral ulcers, are the most common symptom in BD patients whereas fever accompanied by serosal inflammation is the main clinical presentation in FMF patients.

Determination of Genes Related to Uveitis by Utilization of the Random Walk with Restart Algorithm on a Protein-Protein Interaction Network

Uveitis, defined as inflammation of the uveal tract, may cause blindness in both young and middle-aged people. Approximately 10–15% of blindness in the West is caused by uveitis. Therefore, a comprehensive investigation to determine the disease pathogenesis is urgent, as it will thus be possible to design effective treatments. Identification of the disease genes that cause uveitis is an important requirement to achieve this goal. To begin to answer this question, in this study, a computational method was proposed to identify novel uveitis-related genes. This method was executed on a large protein–protein interaction network and employed a popular ranking algorithm, the Random Walk with Restart (RWR) algorithm. To improve the utility of the method, a permutation test and a procedure for selecting core genes were added, which helped to exclude false discoveries and select the most important candidate genes. The five-fold cross-validation was adopted to evaluate the method, yielding the average F1-measure of 0.189. In addition, we compared our method with a classic GBA-based method to further indicate its utility. Based on our method, 56 putative genes were chosen for further assessment. We have determined that several of these genes (e.g., CCL4, Jun, and MMP9) are likely to be important for the pathogenesis of uveitis.