Systemic lupus erythematosus (SLE) is a complex autoimmune disease that causes substantial morbidity. As is typical for many other multifactorial disorders, much of the heritability of SLE remains unknown. We identified a rare autosomal recessive form of SLE, in which autozygome analysis revealed a null mutation in the DNASE1L3 gene. The DNASE1L3-related SLE we describe was always pediatric in onset and correlated with a high frequency of lupus nephritis. Our findings confirm the critical role of impaired clearance of degraded DNA in SLE pathogenesis.

ObjectivesTo characterise the clinical features, immune manifestations and molecular mechanisms in a recently described autoinflammatory disease caused by mutations in TRNT1, a tRNA processing enzyme, and to explore the use of cytokine inhibitors in suppressing the inflammatory phenotype.MethodsWe studied nine patients with biallelic mutations in TRNT1 and the syndrome of congenital sideroblastic anaemia with immunodeficiency, fevers and developmental delay (SIFD). Genetic studies included whole exome sequencing (WES) and candidate gene screening. Patients’ primary cells were used for deep RNA and tRNA sequencing, cytokine profiling, immunophenotyping, immunoblotting and electron microscopy (EM).ResultsWe identified eight mutations in these nine patients, three of which have not been previously associated with SIFD. Three patients died in early childhood. Inflammatory cytokines, mainly interleukin (IL)-6, interferon gamma (IFN-γ) and IFN-induced cytokines were elevated in the serum, whereas tumour necrosis factor (TNF) and IL-1β were present in tissue biopsies of patients with active inflammatory disease. Deep tRNA sequencing of patients’ fibroblasts showed significant deficiency of mature cytosolic tRNAs. EM of bone marrow and skin biopsy samples revealed striking abnormalities across all cell types and a mix of necrotic and normal-appearing cells. By immunoprecipitation, we found evidence for dysregulation in protein clearance pathways. In 4/4 patients, treatment with a TNF inhibitor suppressed inflammation, reduced the need for blood transfusions and improved growth.ConclusionsMutations of TRNT1 lead to a severe and often fatal syndrome, linking protein homeostasis and autoinflammation. Molecular diagnosis in early life will be crucial for initiating anti-TNF therapy, which might prevent some of the severe disease consequences.

The objective of our study was to determine the influence of gender and age of onset on the outcome in Saudi children with systemic lupus erythematosus (SLE). Medical records of children with SLE treated at King Faisal Specialist Hospital and Research Center were reviewed. Outcome measures included Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index score (SLICC/ACR), renal disease requiring dialysis, or transplant and death related to SLE. Patients were classified based on age at disease onset into early onset (<5 years) and late onset (>5 years). Data were analyzed, and comparison was made according to the gender and age groups. Eighty-nine patients (76 female and 13 male) were included. The median disease duration was 5 years. Twelve patients had early-onset disease. There was no difference in the mean age, age at diagnosis, disease duration, and follow-up between the different groups. Logistic regression analysis showed significant association of high SLICC/ACR score with early-onset disease and male gender, while renal disease requiring dialysis and renal transplant was associated significantly with male gender independently of age of disease onset. In contrast, death related to SLE was influenced by early-onset disease. Male children and early onset disease of this cohort had poorer outcome. This finding indicates that gender and early-onset disease influence the long-term outcome of SLE in children.

BACKGROUND AND OBJECTIVEPublished data from Saudi Arabia regarding autoinflammatory diseases are scarce. In this study, we describe the clinical and laboratory features of autoinflammatory diseases in Saudi children.DESIGN AND SETTINGRestrospective, hospital-based study conducted from January 2010 until June 2010.PATIENTS AND METHODSPatients with autoinflammatory disease treated at the Pediatric Rheumatology Clinic at King Faisal Specialist Hospital and Research Center, Riyadh, over the past 10 years were included. Autoinflammatory diseases included the following: familial Mediterranean fever (FMF); chronic recurrent multifocal osteomyelitis (CRMO); early-onset sarcoidosis (EOS); periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis syndrome (PFAPA); chronic infantile neurologic cutaneous and articular syndrome (CINCA); and Muckle-Wells syndrome (MWS). Demographic characteristics, diagnosis, age at onset, disease duration, follow-up duration, clinical and laboratory variables, and outcome data were compiled. Gathered laboratory data were part of patients’ usual medical care.RESULTSThirty-four patients (females, 53%) with autoinflammatory diseases were included (mean age, 151 months. Mean disease duration was 118 months; mean age at onset was 32 months; consanguinity was present in 40%. Patients were diagnosed as follows: FMF, 50%; CRMO, 23.5%; CINCA, 8.8%; EOS, 8.8%; MWS, 6%; and PFAPA, 2.9%. The referral diagnosis was inaccurate in all patients except for FMF patients. Gene study was informative in 9 of 14 FMF patients who had molecular analyses. None of our cohort had amyloidosis. All CRMO patients had a favorable response to treatment except 1 patient, who had refractory, progressive disease. All patients with EOS had multiorgan involvement, including uveitis. All CINCA patients had a favorable response to anakinra.CONCLUSIONOur report shows that autoinflammatory diseases other than FMF may be overlooked. Increased awareness among pediatricians about these conditions will help to provide better health care to patients in the form of early diagnosis and management.

The object of this study was to compare patients with familial versus sporadic systemic lupus erythematosus (SLE) with respect to clinical, laboratory variables and outcome. The familial SLE group comprised 12 patients while the comparative group comprised 24 patients selected by systemic sampling from our pediatric rheumatology clinic database. Those patients are listed according to the date of referral, which represents a sampling frame. The first patient was chosen randomly and subsequent patients were chosen at intervals of three. The two groups were compared with respect to: demographic information, age of onset of SLE, disease and follow up duration, clinical and laboratory variables and outcome. The patients from the familial group were younger and had an earlier age of onset of disease (P = 0.03, 0.001 respectively). Seven patients with familial SLE were from the eastern region of Saudi Arabia (P = 0.006). The two groups were comparable with respect to gender, disease duration and follow-up. At diagnosis, the discoid rash was more frequent in the familial group (P = 0.03) while other clinical and laboratory variables including disease activity as measured by SLEDAI did not show significant differences. The mean dose of steroid and use of other immunosuppressive therapy were similar in both groups. Three patients from the familial group died; two of them had unusual complications (one patient had transverse myelitis and pancreatic pseudocyst and the other one had extensive pyoderma gangrenosum). All patients from the sporadic group are alive in stable condition but one patient had severe central nervous system disease. Familial SLE patients tend to be younger and more likely to have discoid rash, in addition a marked difference in the origin of patients was noted. These differences may be helpful in identifying SLE patients with a stronger genetic predisposition. The mortality among familial SLE patients is more frequent which may reflect the disease severity.