Unusual Presentation of Thrombotic Thrombocytopenic Purpura in a Newly Diagnosed Pediatric Patient With Systemic Lupus Erythematosus in the Setting of MIS-C.

The understanding of coronavirus disease 2019 (COVID-19) immune dysregulation is evolving. Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with alternations in both innate and adaptive immunity, probably caused by a complex interplay of genetics and environmental exposure with various triggers. A rare hematological complication of SLE as well as recently reported in an adult with COVID-19 is thrombotic thrombocytopenic purpura. We report a pediatric case with features suggestive of the multisystem inflammatory syndrome in children with coronary artery ectasia, thrombotic thrombocytopenic purpura, and new-onset SLE.

The genomic landscape of pediatric rheumatology disorders in the Middle East.

The landscape and clinical utility of comprehensive genomic investigations for a wide range of pediatric rheumatic disorders have not been fully characterized in the Middle East. Here, 71 pediatric patients, of diverse Arab origins, were clinically and genetically assessed for a spectrum of rheumatology-related diseases at the only dedicated tertiary children's hospital in the United Arab Emirates. Clinical genomic investigations included mainly (76%) next-generation sequencing-based gene panels and whole-exome sequencing, along with rapid sequencing in the intensive care unit and urgent setting. The overall positive yield was 46.5%, whereas dual diagnoses were made in two cases (3%). Although the majority (21/33, 64%) of positive findings involved the MEFV gene, the remaining (12/33, 36%) alterations were attributed to 11 other genes/loci. Copy number variants (CNVs) contributed substantially (5/33, 15.2%) to the overall diagnostic yield. Sequencing-based testing, specifically rapid sequencing, had a high positive rate and delivered timely results. Genetic findings guided clinical management plans and interventions in most cases (27/33, 81.8%). We highlight unique findings and provide additional evidence that heterozygous loss of function of the IFIH1 gene increases susceptibility to recurrent fevers. Our study provides new insights into the pathogenic variation landscape in pediatric rheumatic disorders.

Coexistence of a novel WISP3 pathogenic variant and an MEFV mutation in an Arabic family with progressive pseudorheumatoid dysplasia mimicking polyarticular juvenile idiopathic arthritis.

BACKGROUND: A spectrum of rare noninflammatory disorders may present with arthropathy that arises from bony dysplasia, a thickened synovium, and noninflammatory effusion, leading to a constellation of clinical features that mimics chronic polyarticular juvenile idiopathic arthritis (JIA). We report a unique Arabic family harboring a novel pathogenic variant in the WISP3 gene and presenting with progressive pseudorheumatoid dysplasia (PPRD), a rare noninflammatory arthropathy mimicking polyarticular JIA. CASE PRESENTATION: An Arabic family with PPRD was diagnosed using whole-exome sequencing (WES), revealing a novel c.707delG pathogenic variant in the WISP3 gene. The proband was referred at 10 years old for possible diagnosis of polyarticular JIA based on progressive arthropathy for three years. He was already on naproxen and methotrexate. We suspected familial noninflammatory arthropathy based on clinical manifestations, imaging findings, and family history. WES confirmed the molecular diagnosis of PPRD in the proband and one sister with a similar phenotype. An unexpected p.A744S MEFV pathogenic variant was detected in the proband, parents, and affected sister. CONCLUSIONS: Early identification and diagnosis of familial noninflammatory arthropathies such as PPRD can prevent unnecessary use of immunosuppressive medications. Diagnosis requires high suspicion in children with early onset arthritic changes, absence of elevated inflammatory markers, specific imaging findings, and positive family history suggestive of an autosomal recessive disorder. We highlight the advantages of WES over single-gene analysis in such cases.

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.

Clinical and genetic association, radiological findings and response to biological therapy in seven children from Qatar with non-bacterial osteomyelitis.

AIM: We aim to report the clinical manifestations, genetic testing results, magnetic resonance imaging (MRI) findings and biologics used in the management of non-bacterial osteomyelitis in our center. METHODS: We conducted a retrospective review of medical records. A previously proposed classification was implemented as follows: chronic recurrent multifocal osteomyelitis (CRMO), chronic non-bacterial osteomyelitis (CNBO) and acute non-bacterial osteomyelitis. RESULTS: Four females and three males with a median age at presentation of 6 years (6 months-14 years) presented with arthralgia (7/7), back pain (4/7), arthritis (4/7) and bone pain (2/7). Six patients had CRMO and one patient had CNBO. Genetic testing revealed an apparent homozygote p.S734L LPIN2 mutation in two siblings, a heterozygote p.M694V MEFV mutation in one patient with familial Mediterranean fever and heterozygote p.Q219H PSTPIPI variant of unknown significance in one patient. The most common lesions on MRI involved the tibia (6/7), talar bones (5/7), fibula (4/7) and sacroiliac joints (4/7). Three patients received infliximab. Two are in remission after 2 and 5 years, and the third was advanced after 5 years to canakinumab. Two other patients received canakinumab first. One patient with Majeed syndrome and dyserythropoietic anemia exhibited evidence of improvement, and one had partial improvement and was then treated with infliximab. CONCLUSION: Non-bacterial osteomyelitis may coexist with other autoinflammatory diseases. MRI remains a favorable diagnostic tool and genetic testing may have a limited role in selected cases. Infliximab and canakinumab are associated with variable outcomes, and 6-week or less dosing intervals for both medications may be more effective.

Overlap of familial Mediterranean fever and hyper-IgD syndrome in an Arabic kindred.

Hyperimmunoglobulinemia D Syndrome (HIDS) has rarely been reported in Arabs. Moreover, the simultaneous presence of mutations in MEFV and MVK segregating in the same family is exceptional. We report an Arabic girl presenting since the age of 8-years with two patterns of recurrent episodes of fever, and associated with a spectrum of clinical features suggestive of overlap between familial Mediterranean fever (FMF) and HIDS. Her 19-year old brother presented since the age of 1 year with prolonged episodes of fever and was diagnosed with HIDS at the age of 7 years based on clinical features and homozygosity for p.V377I mutation in MVK. Shorter episodes of fever and abdominal pain more consistent with FMF ensued since the age of 17 years. Genetic testing done for both patients and all other family members revealed simultaneous presence of mutations in MEFV and MVK but with a variable clinical spectrum ranging from asymptomatic to severe manifestations. Both of our patients are homozygous for p.V377I MVK mutation; the girl is a compound heterozygote for p.E148Q/p.P369S/p.R408G and p.E167D/p.F479L MEFV mutations whereas the brother is a compound heterozygote for p.E148Q/p.P369S/p.R408G and p.M680I MEFV mutations. The clinical implications of having more than one mutation in different genes of monogenic autoinflammatory diseases in the same individual are not clear but may explain atypical clinical manifestations such as the overlap features of both FMF and HIDS in this family.

A novel de novo PSTPIP1 mutation in a boy with pyogenic arthritis, pyoderma gangrenosum, acne (PAPA) syndrome.

Autoinflammatory disorders are a group of Mendelian disorders characterized by seemingly unprovoked inflammatory bouts without high-titer autoantibodies or antigen-specific T-cells and are probably due to defects in the innate immunity. We here report on a 4-year-old Arabic boy with the clinical presentation of an autoinflammatory disorder, namely Pyogenic Arthritis, Pyoderma Gangrenosum and Acne (PAPA) syndrome. The presentation includes abscess formation after immunization and recurrent mono-articular acute arthritis in various joints that responded favourably to systemic glucocorticosteroids, albeit without acne or pyoderma gangrenosum. The mutation analysis of the boy identified a novel de novo mutation in PSTPIP1, the gene responsible for PAPA syndrome. We recommend that the diagnosis of PAPA syndrome should be entertained in the differential diagnosis of patients with recurrent sterile pyogenic arthritis prior to the development of pyoderma gangrenosum or acne in order to initiate a timely management of the disorder.

Clinical and genetic profile of children with periodic fever syndromes from a single medical center in South East Michigan.

OBJECTIVE: To report a cohort of children with periodic fever syndromes (PFS) from Southeast Michigan. METHODS: A retrospective review of medical records for patients referred for periodic fever over 5 years. RESULTS: Sixty-six patients including 21 FMF, 15 PFAPA, four TRAPS and one patient with combined HIDS and FMF were included. In addition, 25 patients were categorized as clinical PFS (cPFS) based on their clinical features however their genetic workup was either negative or inconclusive. Majority of the patients with FMF were from Middle Eastern background (88 %), but positive family history was noted in only 55 % of cases. Mean age at diagnosis was 40.8 months with a mean delay in diagnosis of 24 months. Most common MEFV mutations were p.M694V and p.M694I. Four patients with TRAPS were from mixed European descent and age at onset of symptoms was 6, 12, 12, and 84 months respectively. TNFRSF1A sequence variants in the TRAPS patients included p.R121Q (R92Q) and p.C99G (C70G); one patient had a rare occurrence of a concurrent p.V726A/-MEFV mutation. One patient with HIDS and FMF presented with atypical overlapping PFS clinical manifestations and genetic evaluation showed a unique combination of p.I268T/p.V377I MVK mutations and p.E230K/-MEFV variant. All patients with PFAPA group were from mixed European descent, symptoms started at a mean age of 34.6 months with a mean delay in diagnosis of 23.3 months. Symptoms started during infancy in six patients. All patients fulfilled the diagnostic criteria for PFAPA. The mean age of onset of symptoms in cPFS group was 17.2 months. Empiric colchicine and glucocorticosteroids controlled flares in majority of patients with cPFS. No evidence of amyloidosis was found in this entire cohort of 66 patients after a mean of 29.2 months of follow-up. CONCLUSION: PFS can present with atypical manifestations and should not be excluded based on a negative family history. Concomitant mutations in different autoinflammatory disorders genes can be present and possibly explain atypical manifestations. Various therapies may be considered even if genetic testing is inconclusive or negative.

Granulomatosis with polyangiitis presenting as Henoch-Schönlein purpura in children.

Granulomatosis with polyangiitis (GPA), formerly known as Wegener granulomatosis, in children is an uncommon chronic organ- and life-threatening systemic vasculitis that may share at time of initial presentation a number of clinical features in common with Henoch-Schönlein purpura (HSP), a very common and comparatively benign form of childhood vasculitis. Diagnosis of GPA requires a high index of suspicion, and antineutrophil cytoplasmic antibody tests along with tissue biopsy are helpful tools for diagnosis. We report 2 patients with GPA masqueraded as HSP at time of initial presentation. Both patients presented with nonthrombocytopenic purpura on lower extremities, in addition to abdominal pain, and/or microscopic hematuria and fulfilled both the American College of Rheumatology and the Pediatric Rheumatology European Society classification criteria for HSP. Both patients eventually developed significant renal and pulmonary disease and were diagnosed with GPA. We aim to raise awareness of such atypical presentations of GPA to avoid delayed management.

Inflammatory and noninflammatory arthropathy in patients with 18q deletion syndrome.

A 7-year-old girl with 18q deletion syndrome developed chronic progressive polyarticular inflammatory arthropathy. Atypical features of her arthritis included lack of morning stiffness, absence of pain and discomfort, normal acute-phase reactants, and the presence of clinodactyly, low-set thumbs, metatarsus adductus of her feet, and overriding nontender swollen toes. She had a positive antinuclear antibody test, negative rheumatoid factor and anti-cyclic citrullinated peptide, and undetectable immunoglobulin A level. Magnetic resonance imaging of the right knee and the result of the synovial biopsy were consistent with synovitis. She was treated with naproxen, short course of prednisone, and methotrexate with good clinical response that plateaued over time. We analyzed the scarce reports of inflammatory arthropathy in 18q deletion syndrome and proposed an outline for investigating arthropathies in patients with chromosomal aberrations.

Pachydermatodactyly mimics polyarticular juvenile idiopathic arthritis.

Pachydermatodactyly is an infrequently recognized disorder characterized by painless swelling of the soft tissues around the proximal interphalangeal joints. We report 2 cases erroneously diagnosed as polyarticular juvenile idiopathic arthritis, then referred to pediatric rheumatology for further assessment because of lack of improvement after initial treatment.

Cutaneous polyarteritis nodosa in children.

The purpose of this study was to present the clinical courses and histologic findings of 4 children with cutaneous vasculitis characterized by tender cutaneous nodules and fever in the absence of major organ involvement. We conducted a retrospective chart review of 4 patients with cutaneous vasculitis followed up for a mean of 68 months (range, 12-114 months). The patients included 3 boys and 1 girl (ages at onset, 2-10 years). Clinical and laboratory manifestations included tender erythematous cutaneous nodules (n = 4/4), fever 39 degrees C or higher (4/4), nondeforming arthritis (3/4), leukocytosis and elevated erythrocyte sedimentation rate (4/4), positive antinuclear antibodies (1/4), and elevated streptococcal enzymes (3/4). Skin biopsy results showed inflammation of medium-sized cutaneous arteries with a mixed inflammatory cell infiltrate consistent with cutaneous polyarteritis nodosa (4/4). Patients were treated with prednisone with good initial response, but exacerbation occurred once prednisone was tapered. Additional medications given were methotrexate (2/4), dapsone (2/4), colchicine (1/4), and cyclophosphamide (1/4). One patient is in clinical remission after 48 months of disease; the others have continuing disease that requires treatment. Patients with evidence of streptococcal infection received oral penicillin prophylaxis; two of the three patients had recurrent attacks of vasculitis despite penicillin. No patients have developed major organ system involvement after 12 to 114 months of follow-up. Cutaneous polyarteritis nodosa in children is a recognizable entity characterized by painful nodules, fever, absence of major organ involvement, and chronic or recurrent course. Patients should be screened for streptococcal infection and treated with antibiotics when needed.