Genotype and Phenotype of Adenosine Deaminase 2 Deficiency: a Report from Saudi Arabia.

Adenosine deaminase 2 deficiency (DADA2), a rare and potentially fatal systemic autoinflammatory disease, is characterized by low or lack of ADA2 activity due to ADA2 mutations. DADA2 symptoms are variable and include vasculitis, immunodeficiency, and cytopenia. Minimal data are available from Saudi Arabia. This retrospective study conducted at seven major tertiary medical centers examined the phenotypic and genotypic variabilities, clinical and diagnostic findings, and treatment outcomes among 20 Saudi patients with DADA2 from 14 families. The median age of the study cohort was 9.5 years (4-26 years). The clinical presentation was before the age of 5 months in 25% of patients. Homozygous c.1447-1451del mutation was the most frequent ADA2 alteration (40%), followed by c.882-2A:G (30%). All tested patients exhibited absent or near-absent ADA2 activity. Phenotypic manifestations included stroke (40%), hematological abnormalities (95%), lymphoproliferation (65%), and recurrent infection (45%). Five and three patients had extracranial vasculitis features and Hodgkin lymphoma, respectively. Atypical manifestations included growth retardation (30%) and transverse myelitis. Anti-tumor necrosis factor (anti-TNF) therapy was the main treatment. Some patients underwent blood transfusion, splenectomy, cyclosporine and colony-stimulating factor therapies, and hematopoietic stem cell transplantation due to anti-TNF therapy failure. Fulminant hepatitis and septic multiorgan failure caused mortality in three patients. Thus, this study revealed the variability in the molecular and clinical characteristics of DADA2 in the study cohort with predominant aberrant hematological and immunological characteristics. Consensus diagnostic criteria will facilitate early diagnosis and treatment. Additionally, disease registries or large prospective studies are needed for evaluating rare disease complications, such as cancer.

Consensus clinical approach for a newly diagnosed systemic juvenile idiopathic arthritis among members of the pediatric rheumatology Arab group.

BACKGROUND: Systemic juvenile idiopathic arthritis (sJIA) is a diagnosis of exclusion. The complex nature and clinical variety of the disease, as well as the vast clinical variation of disease presentation, may lead to difficulties in disease detection and subsequent delays in treatment. AIM: To provide a consensus guidance on the management of newly diagnosed sJIA patients among pediatric rheumatologists in Arab countries. METHODS: This work was conducted in two phases. The first phase utilized an electronic survey sent through an email invitation to all pediatric rheumatologists in Arab countries. In the second phase, a Task Force of ten expert pediatric rheumatologists from Arab countries met through a series of virtual meetings. Results obtained in phase one were prioritized using a nominal group and Delphi-like techniques in phase two. RESULTS: Seven overarching principles and a set of recommendations were approved by the Task Force to form the final consensus. CONCLUSION: This is the first consensus on a clinical approach for pediatric rheumatic diseases among Arab pediatric rheumatologists. It is presented as a guidance on the clinical approach to sJIA that requires further evidence, and future updates are anticipated.

New or vanishing frontiers: LACC1-associated juvenile arthritis.

BACKGROUND: The classification and pathogenic basis of juvenile idiopathic arthritis (JIA) are a subject of some controversy. Essentially, JIA is an exclusion diagnosis that represents a phenotypically heterogeneous group of arthritis of unknown origin. Familial aggregation of JIA supports the concept of genetic influence in the pathogenesis of JIA. OBJECTIVE: To present the spectrum of laccase domain-containing 1 (LACC1)-associated juvenile arthritis with clinical, biochemical, and molecular genetic data of a cohort of 43 patients, including 11 previously unpublished cases. METHODS: We studied 11 patients with different categories of juvenile idiopathic arthritis from 5 consanguineous families, all from Saudi Arabia, except 2 patients who were of Jordanian ethnicity. Whole-exome sequencing was used to identify the disease-causing variant of LACC1. We also reviewed the clinical spectrum and molecular genetic data of previously published cases of LACC1-associated juvenile arthritis. RESULTS: This study describes 43 (29 females, 14 males) patients from consanguineous multiplex families. Most of the included patients were of Arab origin with 86% having early onset disease. The most frequent categories were systemic (19 patients) and rheumatoid factor-negative polyarticular (19 patients). Thirty-seven (86%) had progressive erosive arthritis and 10 (23.3%) had persistent limb lymphedema. None of the patients had features of macrophage activation syndrome. Genetic analysis confirmed LACC1 variant in all patients; 22 patients had common founder mutation (LACC1: c.850T > C,p.C284R), while the others showed different LACC1 variants. All patients were treated aggressively with methotrexate and sequential biologic agents. Most of them showed a poor response to treatment. CONCLUSION: This report expands the pathogenic variants of LACC1 and the clinical spectrum associated with this genetic subset of juvenile arthritis. The predominance of autosomal-recessive inheritance and strong genetic evidence allowed us to propose LACC1-associated juvenile arthritis as a distinct disorder.

Pattern and diagnostic evaluation of systemic autoinflammatory diseases other than familial Mediterranean fever among Arab children: a multicenter study from the Pediatric Rheumatology Arab Group (PRAG).

To define the spectrum and phenotypic characteristics of systemic autoinflammatory diseases (SAIDs) other than familial Mediterranean fever (FMF) in Arab children and to delineate diagnostic evaluation. Data retrospectively collected on patients with clinical and/or genetically proven SAIDs other than FMF at 10 tertiary Arab pediatric rheumatology clinics from 1990 to 2018. The collected data comprised the clinical findings and diagnostic evaluation including genetic testing, the provided treatment and the accrual damage related to SAIDs. A total of 144 patients (93 female) with a median age at onset of 2.5 (range 0.1-12) years were enrolled. The initial diagnosis was inaccurate in 49.3%. Consanguinity rate among parents was 74.6%. The median time-to-diagnosis for all SAIDs was 2.5 (range 0.1-10) years. There were 104 patients (72.2%) with a confirmed diagnosis and 40 patients with suspected SAIDs. Seventy-two had monogenic and 66 patients with multifactorial SAIDs while six patients had undifferentiated SAIDs. The most frequent monogenic SAIDs were LACC1 mediated monogenic disorders (n = 23) followed by CAPS (12), TRAPS (12), HIDS (12), and Majeed's syndrome (6). The most frequent multifactorial SAIDs was CRMO (34), followed by PFAPA (18), and early onset sarcoidosis (EOS) (14). Genetic analysis was performed in 69 patients; 50 patients had genetically confirmed disease. Corticosteroid used for 93 patients while biologic agents for 96 patients. Overall, growth failure was the most frequent accrual damage (36%), followed by cognitive impairment (13%). There were three deaths because of infection. This study shows a heterogenous spectrum of SAIDs with a high number of genetically confirmed monogenic diseases; notably, LACC1 associated diseases. Hopefully, this work will be the first step for a prospective registry for SAIDs in Arab countries.

Biologic agents therapy for Saudi children with rheumatic diseases: indications and safety.

OBJECTIVE: To report the indications and safety of biologic agents in childhood rheumatic diseases at a tertiary hospital. METHODS: Children with rheumatic diseases treated with biologic agents at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia, from January 2001 to December 2011 were included. All patients were reviewed for: demographic characteristics, diagnosis, concomitant treatment and indications of using biologic agents, age at start of therapy and side effects during the treatment period. RESULTS: In all, 134 children (89 female) with various rheumatic diseases were treated with biologic agents. Mean age at starting biologic treatment was 9.3 (4.25-14) years and mean therapy duration was 14.7 (3-88) months. Juvenile idiopathic arthritis (JIA) was the most frequent diagnosis (70.1%) followed by systemic lupus erythematosus (12.7%) and vasculitis (4.5%). All patients received concomitant therapy (corticosteroids and disease-modifying antirheumatic drugs). In total, 273 treatments with biologic agents were used, (95 etanercept, 52 rituximab, 47 adalimumab, 37 infliximab, 23 anakinra, 10 tocilizumab and nine abatacept). Therapy was switched to another agent in 57 (42.5%) patients, mainly because of inefficacy (89.4%) or adverse event (10.6%). A total of 95 (34.8%) adverse events were notified; of these, the most frequent were infusion-related reactions (33.7%) followed by infections (24.2%) and autoantibody positivity (10.6%). One patient developed macrophage activation syndrome. CONCLUSION: Biologic agents were used in children with a range of rheumatic diseases. Of these, the most frequent was JIA. Off-label use of biologic agents in our cohort is common. These agents seem safe. However, they may associated with various adverse events. Sequential therapy seems well tolerated. However, this should be carefully balanced and considered on an individual basis.

A retrospective review of autoinflammatory diseases in Saudi children at a rheumatology clinic.

BACKGROUND AND OBJECTIVE: Published 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 SETTING: Restrospective, hospital-based study conducted from January 2010 until June 2010. PATIENTS AND METHODS: Patients 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. RESULTS: Thirty-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. CONCLUSION: Our 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.