Evaluation of pediatric rheumatologists' approach to rituximab use: a questionnaire study.

Rituximab (RTX) is a chimeric monoclonal antibody that targets the CD20 antigen on B cells and is used in various autoimmune disorders. In this study, we aimed to measure the awareness of pediatric rheumatologists about the use of RTX through a survey. Between February and March 2023, a 42-question survey was sent via email to pediatric rheumatology specialists in Turkey. The participants were questioned for which diagnoses and system involvement they preferred to use RTX, which routine tests they performed, vaccination policy, and adverse events that occurred during or after infusion. Forty-one pediatric rheumatologists answered the survey. They prescribed RTX most frequently for systemic lupus erythematosus (87.8%) and ANCA-associated vasculitis (9.8%). Prior to the administration of RTX, 95% of clinicians checked renal and liver function tests, as well as immunoglobulin levels. The most frequently tested hepatitis markers before treatment were HBsAg and anti-HBs antibody (97.6%), while 85.4% of rheumatologists checked for anti-HCV. Clinicians (31.4%) reported that they postpone RTX infusion 2 weeks following an inactivated vaccine. Sixty-one percent of rheumatologists reported starting RTX treatment 1 month after live vaccines, while 26.8% waited 6 months. The most frequent adverse events were an allergic reaction during RTX infusion (65.9%), hypogammaglobulinemia (46.3%), and rash (36.6%). In the event of hypogammaglobulinemia after RTX treatment, physicians reported that they frequently (58.5%) continued RTX after intravenous immunoglobulin administration. CONCLUSIONS: RTX has become a common treatment option in pediatric rheumatology in recent years. Treatment management may vary between clinician such as vaccination and routine tests. WHAT IS KNOWN: • During the course of rituximab therapy, clinicians should be attentive to specific considerations in pre-treatment, during administration, and in post-treatment patient monitoring. WHAT IS NEW: • There are differences in practice among clinicians in the management of RTX therapy. These practice disparities have the potential to impact the optimal course of treatment. • This study highlights that standardized guidelines are needed for RTX treatment in pediatric rheumatology, particularly for vaccination policies and routine tests.

A clinical overview of paediatric sarcoidosis: Multicentre experience from Turkey.

OBJECTIVES: We aimed to outline the demographic data, clinical spectrum, and treatment approach of sarcoidosis in a large group of patients and sought to figure out the variations of early-onset (EOS) and late-onset paediatric sarcoidosis (LOS). METHODS: The study followed a retrospective-descriptive design, with the analysis of medical records of cases diagnosed as paediatric sarcoidosis. RESULTS: Fifty-two patients were included in the study. The median age at disease onset and follow-up duration were 83 (28.2-119) and 24 (6-48) months, respectively. Ten (19.2%) cases had EOS (before 5th birthday) and 42 (80.7%) cases had LOS. The most common clinical findings at the time of the disease onset were ocular symptoms (40.4%) followed by joint manifestation (25%), dermatological symptoms (13.5%), and features related to multi-organ involvement (11.5%). Anterior uveitis was the most common (55%) one among ocular manifestations. Patients with EOS displayed joint, eye, and dermatological findings more commonly than patients with LOS. The recurrence rate of disease in patients with EOS (5.7%) and LOS (21.1%) were not statistically different (P = .7). CONCLUSIONS: Patients with EOS and LOS may present with variable clinical features and studies addressing paediatric sarcoidosis cases in collaboration between disciplines will enhance the awareness of this rare disease among physicians and assist early diagnosis with lesser complications.

Do the features of juvenile psoriatic arthritis change according to age? A comprehensive evaluation of the PeRA Research Group Registry.

OBJECTIVES: To describe the clinical features and treatment outcomes of children with juvenile psoriatic arthritis (JPsA) and to compare the distinct patterns of the disease between early-onset and late-onset age groups. METHODS: Patients with JPsA followed regularly for at least 6 months between 2010-2020 in 7 pediatric rheumatology centers in Turkey were included in the study. The demographic features, clinical manifestations, treatment strategies, and outcomes of the patients were evaluated retrospectively. RESULTS: Eighty-seven (46 male/41 female) patients were included in the study. The mean age at diagnosis was 11.9 ± 4.5. Fifty-seven (65.5%) patients had psoriasis at the time of diagnosis, arthritis preceded psoriasis in 10 (11.5%) patients. Thirty (34.5%) patients had dactylitis, 28 (32.2%) had nail pitting, 36 (41.4%) had involvement of the small joints, 20 (23%) had enthesitis. Sacroiliitis was detected in 11 (12.6%) patients by magnetic resonance imaging. Anti-nuclear antibodies (ANA) were positive in 35 (40.2%) patients. Twelve children (%13.8) were in the early-onset (<5 years) group. Uveitis and ANA positivity were more common in the early-onset group. Active joint counts and activity scores of our patients showed significant improvement at 6th month and at the last control compared with baseline. CONCLUSION: About one-third of patients with JPsA do not have psoriasis at the time of diagnosis. In some patients, no skin lesion is seen during the course of the disease. Children with psoriatic arthritis seem to display two different phenotypes. Younger children have female predominance, ANA positivity, and uveitis, while older children have more axial involvement.

Does having MEFV gene sequence variants affect the clinical course and colchicine response in children with PFAPA syndrome?

The primary aim of this study was to document the treatment modalities used in periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome and look for the efficacy and safety of colchicine in the treatment of PFAPA patients. The secondary aim was to search for whether having MEFV (Mediterranean fever) gene sequence variants affect the clinical course and response to colchicine. The study was conducted in 2 pediatric rheumatology centers. The patients that have been diagnosed with PFAPA syndrome between December 2017 and December 2021 were evaluated retrospectively. The study included 157 patients with PFAPA syndrome (54.8% boys and 45.2% girls). The median follow-up duration was 18 (IQR: 12-30) months. One hundred and fifty-five patients (98.7%) had exudative pharyngitis, 120 patients (76.4%) had aphthous stomatitis, and 82 patients (52.2%) had cervical lymphadenitis during the attacks. Clinical features during attacks were not affected by the presence or absence of the MEFV gene sequence variants. Corticosteroid treatment during attacks was given to 152 patients (96.8%). The frequency of fever attacks did not change in 57 patients (37.5%), increased in 57 patients (37.5%), and decreased in 38 patients (25%) after corticosteroid use. Colchicine was given to 122 patients (77.7%) in the cohort. After colchicine treatment, complete/near-complete resolution of the attacks was observed in 57 patients (46.7%). Colchicine led to partial resolution of the attacks in 59 patients (48.4%). In only 6 patients (4.9%), no change was observed in the nature of the attacks with colchicine treatment. The median duration of the attacks was 4 (IQR: 4-5) days before colchicine treatment, and it was 2 (IQR: 1-2.5) days after colchicine treatment. Also, a significant decrease in the frequency of the attacks was observed before and after colchicine treatment [every 4 (IQR: 3-4) weeks versus every 10 (IQR: 8-24) weeks, respectively, (p < 0.001)]. The overall response to colchicine was not affected by MEFV sequence variants. It was seen that the frequency of fever attacks decreased dramatically in both groups, and children with MEFV variants had significantly less attacks than children without MEFV variants after colchicine treatment (every 11 weeks vs every 9.5 weeks, respectively, p: 0.02). CONCLUSION: Colchicine seems to be an effective and safe treatment modality in PFAPA treatment. It led to a change in the nature of the attacks either in the frequency, duration, or severity of the attacks in 95.1% of the patients. This study has shown that having MEFV gene sequence variants did not affect the clinical course or response to colchicine. We recommend that colchicine should be considered in all PFAPA patients to see the response of the patient, irrespective of the MEFV gene mutations. WHAT IS KNOWN: • Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome is the most common periodic fever syndrome in the world. Familial Mediterranean fever (FMF) is the most common cause of periodic fever syndrome in Turkey. • Colchicine has become a new treatment option in PFAPA. WHAT IS NEW: • Some PFAPA patients have Mediterranean fever (MEFV) gene variants, and it is speculated that PFAPA patients with MEFV gene mutations respond better to colchicine. • The aim of this study was to look for this hypothesis. We have seen that the clinical phenotype and colchicine response of PFAPA patients were not affected by MEFV gene sequence variants.

Cluster analysis of paediatric Behçet's disease: Data from The Pediatric Rheumatology Academy-Research Group.

OBJECTIVES: Behçet's disease (BD) is a systemic vasculitis affecting many organ systems, with the involvement of all-sized arteries and veins. The study aims to determine the main characteristics of paediatric BD patients and also analyse the clustering phenotypes. METHODS: Demographic data, clinical manifestations, laboratory features, treatment schedules, and disease outcomes were achieved from patients' charts retrospectively. A cluster analysis was performed according to the phenotype. RESULTS: A total of 225 (109 male/116 female) patients with BD were enrolled in the study. The median ages of disease onset and diagnosis were 131 (36-151) and 156 (36-192) months, respectively. According to cluster analysis, 132 (58.6%) patients belonged to the mucocutaneous-only cluster (C1), while 35 (15.6%) patients fitted to articular type (C2), 25 (11.1%) were in the ocular cluster (C3), 26 (11.6%) were in the vascular cluster (C4), and 7(3.1%) belonged to the gastrointestinal cluster (C5). Ocular and vascular clusters were more common in boys (p < .001), while girls usually presented with the mucocutaneous-only cluster. The disease activity at the diagnosis and the last control was higher in ocular, vascular, and gastrointestinal clusters. CONCLUSIONS: These identified juvenile BD clusters express different phenotypes with different outcomes Our analysis may help clinicians to identify the disease subtypes accurately and to arrange personalized treatment.

PREDICT-crFMF score: A novel model for predicting colchicine resistance in children with familial Mediterranean fever.

OBJECTIVES: To develop a novel scoring system to predict colchicine resistance in Familial Mediterranean fever (FMF) based on the initial features of the patients. METHODS: The medical records of patients were analyzed prior to the initiation of colchicine. After generating a predictive score in the initial cohort, it was applied to an independent cohort for external validation of effectiveness and reliability. RESULTS: Among 1418 patients with FMF, 56 (3.9%) were colchicine resistant (cr) and 1312 (96.1%) were colchicine responsive. Recurrent arthritis (4 points), protracted febrile myalgia (8 points), erysipelas-like erythema (2 points), exertional leg pain (2 points), and carrying M694V homozygous mutation (4 points) were determined as the parameters for predicting cr-FMF in the logistic regression model. The cut-off value of 9 was 87% sensitive and 82% specific to foresee the risk of cr-FMF in the receiver operating characteristic. Validation of the scoring system with an independent group (cr-FMF = 107, colchicine responsive = 1935) revealed that the cut-off value was 82% sensitive and 79% specific to identify the risk of cr-FMF. CONCLUSIONS: By constructing this reliable and predictor tool, we enunciate that predicting cr-FMF at the initiation of the disease and interfering timely before the emergence of complications will be possible.

Clinical characteristics and predictors for recurrence in chronic nonbacterial osteomyelitis: a retrospective multicenter analysis.

Background/aim: Chronic nonbacterial osteomyelitis (CNO) is a rare disease of unknown etiology and most commonly occurs during childhood or adolescence. The purpose of this study is to collect data on the clinical features, outcomes, and management of the disease and to identify the factors affecting recurrence. Materials and methods: This is a retrospective multicenter cross-sectional study of pediatric patients diagnosed with CNO. A total of 87 patients with a diagnosis of CNO followed for at least 6 months in 8 pediatric rheumatology centers across the country between January 2010 and December 2021 were included in this study. Results: The study included 87 patients (38 girls, 49 boys; median age: 12.5 years). The median follow-up time was 20 months (IQR: 8.5-40). The median time of diagnostic delay was 9.9 months (IQR: 3-24). Arthralgia and bone pain were the most common presenting symptoms. Multifocal involvement was detected in 86.2% of the cases and a recurrent course was reported in one-third of those included in the study. The most commonly involved bones were the femur and tibia. Vertebrae and clavicles were affected in 19.5% and 20.6% of cases, respectively. The erythrocyte sedimentation rate (ESR) values of 60.9% of the patients were above 20 mm/h and the C-reactive protein values of 44.8% were above 5 mg/L. The remission rate was 13.3% in patients using nonsteroidal antiinflammatory drugs and 75.0% in those using biological drugs. Vertebral and mandibular involvement and high ESR values at the time of diagnosis were associated with recurrence. Conclusion: In this multicenter study, CNO with vertebral and mandibular involvement and high ESR at diagnosis were associated with recurrence.

Hepatitis B vaccination response of treatment-naive patients with juvenile idiopathic arthritis.

To evaluate the vaccine response of treatment-naive juvenile idiopathic arthritis (JIA) patients who were fully vaccinated against Hepatitis B Virus (HBV) and then compare their antibody status with healthy controls. In this multicenter study, initial visit hepatitis B surface antigen (HbsAg) and anti-hepatitis B surface antibody (anti-Hbs) titers of 262 treatment-naive JIA patients who were followed up regularly between May 2015 and October 2019 were evaluated retrospectively from patients' medical records and compared with 276 healthy peers. Both HbsAg and anti-Hbs antibody titers were tested by the ELISA technique. Anti-HBs titers ≥ 10 IU/L were considered as reactive indicating seroprotection against HBV. In the JIA group, seropositivity rate was 59.1% while 72.9% of the control group were immune against HBV (p = 0.002). The median titer for anti-Hbs was 14 (range: 0-1000) IU/L in the patient group and 43.3 (range: 0-1000) IU/L in the control group (p = 0.01). Neither JIA patients nor healthy controls were positive for HbsAg. Patients with JIA vaccinated according to the national vaccination schedule were evaluated at their first visit in pediatric rheumatology outpatient clinics for anti-Hbs presence and it was found that they have lesser seroprotectivity than their age and sex-matched routinely vaccinated, healthy peers. So, to complete missing vaccines and booster vaccine doses, assessing the immune status of the patients at the time of diagnosis against HBV should be in the check-list of physicians dealing with pediatric rheumatic diseases.

Adherence to best practice consensus guidelines for familial Mediterranean fever: a modified Delphi study among paediatric rheumatologists in Turkey.

BACKGROUND: Although not validated fully, recommendations are present for diagnosis, screening and treatment modalities of patients with familial Mediterranean fever (FMF). OBJECTIVE: To review the current practices of clinicians regarding FMF and reveal their adherence to consensus guidelines. METHODS: Fifteen key points selected regarding the diagnosis and management of FMF were assessed by 14 paediatric rheumatologists with a three-round modified Delphi panel. RESULTS: Consensus was reached on the following aspects: genetic analysis should be ordered to all patients when clinical findings support FMF, but its result is not decisive alone. In the absence of clinical features, colchicine should be commenced when two pathogenic alleles and family history of amyloidosis are present. Serum amyloid A testing at each visit is recommended in patients resistant to colchicine, with subclinical inflammation and family history of amyloidosis. Consensus was reached on both the definition of colchicine resistance and starting biologic in resistant cases. Cost, efficiency, ease of use, treatment adherence, accessibility and emergence of adverse events are the factors affecting the choice of biologic agents. In patients without any attack and evidence of subclinical inflammation within the last 6 months following initiation of biologics, treatment dose intervals can be prolonged. CONCLUSION: A consensus was achieved regarding the routine diagnosis and screening and treatment of FMF patients. The definition of colchicine resistance was made and a protocol was created for prolongation of treatment intervals of biologic agents. We anticipate that the results of the study reveal real-life data on the approach to patients in clinical practice.

Differences and similarities of multisystem inflammatory syndrome in children, Kawasaki disease and macrophage activating syndrome due to systemic juvenile idiopathic arthritis: a comparative study.

To compare the clinical and laboratory findings of multisystem inflammatory syndrome in children (MIS-C), patients with Kawasaki disease (KD) and with macrophage activating syndrome due to systemic juvenile idiopathic arthritis (sJIA-MAS) on real-life data. Patients diagnosed with MIS-C, KD, and sJIA-MAS from 12 different centers in Turkey who were followed for at least 6 months were included in the study. Demographic, clinical, and laboratory findings of all patients were analyzed. A total of 154 MIS-C, 59 KD, and 31 sJIA-MAS patients were included. The median age of patients with MIS-C were higher than those with KD while lower than those with sJIA-MAS (8.2, 3, 12 years, respectively). Myalgia (39.6%), cardiac (50.6%), gastrointestinal (72.7%), and neurological (22.1%) involvements were more common in patients with MIS-C compared to others. MIS-C patients had lower levels of lymphocyte (950 vs 1700 cells/µl) and thrombocyte (173,000 vs 355,000 cells/µl) counts and higher pro-BNP (1108 vs 55 pg/ml) levels than KD. Ferritin levels were higher in patients with MIS-C compared to patients with KD while they were lower than patients with sJIA-MAS (440, 170, 10,442 ng/ml, respectively). Patients with MIS-C had a shorter duration of hospitalization than sJIA-MAS (p = 0.02) while they required intensive care unit admission more frequently (55 vs 8 patients, p < 0.001). The median MAS/sJIA score of MIS-C patients was - 1.64 (- 5.23 to 9.68) and the median MAS/sJIA score of sJIA-MAS patients was -2.81 ([- 3.79] to [- 1.27]). MIS-C patients displayed certain differences in clinical and laboratory features when compared to KD and sJIA-MAS. Definition of the differences and similarities between MIS-C and the other intense inflammatory syndromes of childhood such as KD and MAS will help the clinicians while making timely diagnosis.

The analysis of genotype-phenotype correlation in familial Mediterranean fever.

BACKGROUND: Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease manifesting with phenotypic heterogeneity. It is a clinically diagnosed disease supported by Mediterranean fever gene mutation analysis. This medical record review study aimed to make a new interpretation of clinical features in FMF patients by grouping genetic results based on the classification proposed by the Eurofever/ Paediatric Rheumatology International Trials Organisation. METHODS: The medical charts of pediatric FMF patients who were diagnosed and followed up regularly at the two pediatric rheumatology units were reviewed. Genetic analysis results were classified as confirmatory and nonconfirmatory as defined in the new Eurofever/ Paediatric Rheumatology International Trials Organisation classification criteria, and they were compared with clinical findings. RESULTS: A total of 216 FMF patients were involved in the study. Group 1 was composed of 133 (61.6%) patients with a confirmatory mutation and group 2 included 83 (38.4%) patients with a nonconfirmatory mutation. All clinical findings were compared, and in terms of fever (P = 0.027), abdominal pain (P = 0.016), arthritis (P = 0.008) and erysipelas-like erythema (ELE; P = 0.003) incidence, there was a significant difference between the two groups. The most common Mediterranean fever gene mutation patterns were homozygous (33.8%) and heterozygous (17.1%) mutations of M694V. The frequency of arthritis and ELE in patients with M694V homozygous mutations was significantly higher than in the other patients (P = 0.002 and P <0.001, respectively). CONCLUSIONS: The most frequently observed clinical features of FMF (i.e., fever and abdominal pain) are both observed in patients with confirmatory and nonconfirmatory mutations, ELE and arthritis are more commonly observed in patients with confirmatory mutations.

Low disease activity state in juvenile-onset systemic lupus erythematosus.

OBJECTIVES: To determine the rate of achieving The Lupus Low Disease Activity State (LLDAS) in children with systemic lupus erythematosus (SLE) for tracing pertinent treatment modalities. METHODS: A total of 122 juvenile-onset SLE (jSLE) patients from six pediatric rheumatology centers in Turkey were enrolled in the study. LLDAS-50 was defined as encountering LLDAS for at least 50% of the observation time. According to the achievement of LLDAS-50, clinical features, immunological profiles, and treatments of patients with jSLE have been revealed. RESULTS: LLDAS of any duration was achieved by 82% of the cohort. Although only 10.8% of the patients achieved remission, 68.9% reached LLDAS-50. A significant difference was found between patients who reached LLDAS-50 and those who did not, in terms of the time to reach low-dose corticosteroid treatment (p = 0.002), the presence of subacute cutaneous findings (p = 0.007), and the presence of proteinuria (p = 0.002). Both of the groups were under similar treatment approaches. However, the number of patients being treated with corticosteroids at the last visit was found to be significantly higher in patients who achieved LLDAS-50 (p<0.001). CONCLUSION: Targeting LLDAS in jSLE, even with long-term, low-dose corticosteroid use, seems to be an achievable goal in clinical practice.

The feasibility of withdrawing canakinumab in paediatric colchicine-resistant familial Mediterranean fever patients.

OBJECTIVES: To determine the feasibility of withdrawing canakinumab (CAN) in a large cohort of paediatric patients with colchicine-resistant familial Mediterranean fever (crFMF). METHODS: This retrospective observational cohort study included paediatric crFMF patients that received CAN treatment for ≥6 months. Patient data were recorded at treatment onset (baseline), and at 1, 3, 6, 12, 18, and 24 months after initiation of treatment. RESULTS: The study included 114 patients that were followed-up for 2736 person-months. During the 24-month follow-up period, the CAN dose interval remained unchanged in 44 patients. The dose interval was extended in 58 patients within a median 6 months (range: 3-18 months) of treatment initiation. In all, 4 of these 58 patients had a new attack of crFMF after the dose interval was extended. CAN was withdrawn in 12 patients (in 5 at month 12 month and in 7 at month 18), of which 2 had a new attack within 3 months of withdrawal. In these 2 patients CAN was re-initiated with a dose interval of 8 weeks. The remaining 10 patients in which CAN was withdrawn did not report any symptoms throughout the remainder of the 24-month follow-up period. The median attack-free period in those treated with CAN was 669 d (95% CI: 644-696). CONCLUSIONS: The present findings show that it may be feasible to withdraw CAN or extend its dose interval in paediatric crFMF patients. Based on the present findings, we think that as the quantity of real-life data increases, standard CAN protocols may be developed.

Protracted febrile myalgia syndrome as the first manifestation of familial Mediterranean fever in children: case-based review.

Protracted febrile myalgia syndrome (PFMS) is one of the rare conditions characterized by long standing severe myalgia and fever in familial Mediterranean fever (FMF) patients. Laboratory studies show elevated values of inflammatory markers and normal creatinine phosphokinase (CPK) levels. Rarely, PFMS may be the first manifestation of FMF and this makes the diagnosis of FMF and PFMS challenging. The aim of this report was to describe case series of PFMS patients without previous diagnosis of FMF and discuss with other pediatric PFMS cases described in the literature. Six patients with PFMS as the first manifestation of FMF from two Pediatric Rheumatology clinics were presented. The male: female ratio was 1:1. The median (min-max) age at diagnosis was 7.05 (5.5-15.5) years. All patients had severe myalgia. No fever was detected in two patients. Only one patient had rash. Markedly elevated acute phase reactants were observed in all patients. CPK levels were normal in all patients. Also, we searched the PubMed/MEDLINE, Google Scholar, Web of Science and Scopus databases from inception to May 2020, using the keywords 'familial Mediterranean fever, protracted febrile myalgia, child' and 52 pediatric PFMS were found. In the literature, three patients did not have fever, and nineteen patients were not previously diagnosed with FMF as our patients. As a conclusion, PFMS may be the first manifestation of FMF. It should be suspected in cases with prolonged severe myalgia with or without fever, and high acute phase reactants.

The influence of carrying MEFV gene variants on juvenile systemic lupus erythematosus.

Juvenile-onset systemic lupus erythematosus (jSLE) patients typically have a more severe disease course than adults with SLE. We aimed to assess the prevalence and disease course of jSLE patients carrying MEFV variants. MEFV variant analyses were performed in 44 jSLE patients and effect of these variants on disease severity and course was analyzed by SLEDAI score and SLICC/ACR index. Ten of the patients (22.7%) had a MEFV variant. The median (min-max) SLEDAI score and SLICC/ACR index were 2(0-13) and 0(0-3), respectively. Median age at disease onset, disease duration, SLICC/ACR indexes, SLEDAI scores, clinical and laboratory findings of the patients were comparable in carriers of variants and non-carriers. Nineteen patients (43.2%) had biopsy-proven lupus nephritis and four of these patients had MEFV variants. There was no significant difference between patients with and without MEFV carriers in terms of lupus nephritis. Even though not significant statistically, renal involvement was milder in MEFV carriers than non-carriers. The presence of MEFV variants does not increase the overall susceptibility to jSLE in our cohort, while larger number of patients is required to display the protective role of MEFV variants in jSLE.

Comorbidities and phenotype-genotype correlation in children with familial Mediterranean fever.

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease manifesting with phenotypic heterogeneity. The phenotype-genotype correlation is not established clearly yet. Furthermore, some comorbidities such as vasculitis and inflammatory arthritis may accompany FMF. Herein, we aimed to define phenotype-genotype correlation and comorbid diseases of children with FMF. The medical records of 1687 children diagnosed and followed up as FMF were reviewed retrospectively. Disease severity was assessed by PRAS score. A total of 1687 children (841 girls, 846 boys) were involved in the study. The mean ± standard deviation of current age, age at symptom onset, and age at diagnosis were 13.1 ± 5.4, 5.4 ± 4, and 8 ± 4.2 years, respectively. Median (min-max) follow-up period was 3 (0.5-18) years. Among them, 118 (7%) patients had at least one concomitant disease and 72% of them were carrying at least one M694V mutation. Patients with a concomitant disease expressed a more severe course of disease when compared to ones without a concomitant disease (23.7% vs 8.8%, p < 0.001). Children carrying homozygous M694V mutation had significantly earlier age of disease onset and severe disease course (p < 0.001). Forty-four patients (2.6%) were colchicine resistant and most of them were carrying homozygous M694V mutation. Sixteen colchicine-resistant patients were treated with anakinra while 28 received canakinumab. Juvenile idiopathic arthritis (JIA) and immunoglobulin A vasculitis were the most commonly seen associated diseases and the patients with a concomitant disease demonstrated more severe course. This is the largest pediatric cohort studied and presented since now. We confirmed that carrying M694V mutation is associated both with a severe disease course and a predisposition to comorbidities.

Comparison of Pediatric Familial Mediterranean Fever Patients Carrying Only E148Q Variant With the Ones Carrying Homozygous Pathogenic Mutations.

OBJECTIVE: The aims of this study were to compare demographic data, clinical features, and severity scores of familial Mediterranean fever patients carrying E148Q variant with the patients having homozygous pathogenic MEFV mutations and to evaluate both of these groups for the performance of Tel-Hashomer, Livneh, and pediatric diagnostic criteria. METHODS: The demographic and clinical data of patients with familial Mediterranean fever either heterozygous or homozygous for E148Q variant (group 1) and patients with homozygous mutations (M694V, M694I, M680I, V726A) (group 2) were collected retrospectively. All patients were evaluated for 3 diagnostic criteria. RESULTS: E148Q variant was present in 128 patients (22.9%), 112 of whom had heterozygous and 16 of whom had homozygous E148Q mutation. Group 2 had 430 patients (77.1%), 372 of whom had homozygous M694V mutation, 50 of whom had homozygous M680I mutation, 5 of whom had homozygous V726A mutation, and 3 of whom had homozygous M694I mutation. Pleuritis, arthritis, recurrent fever, erysipelas-like erythema, and anemia were significantly more common in group 2 than group 1 (p < 0.05). Moderate and severe Pras scores were significantly higher in group 2 (p < 0.001). During attack-free periods, C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A were found significantly higher in group 2 than in group 1 (p < 0.05). The percentage of children diagnosed according to Tel-Hashomer and pediatric criteria was significantly higher in group 2 than in group 1 (p < 0.05). Both groups show similar diagnostic utility by Livneh criteria. CONCLUSIONS: Children with the E148Q variant met the 3 diagnostic criteria; they had a milder disease course both clinically and in laboratory means.

The Value of Serum Amyloid A Levels in Familial Mediterranean Fever to Identify Occult Inflammation During Asymptomatic Periods.

OBJECTIVE: The aim of this observational study was to evaluate whether there was any correlation between the acute phase reactants in children with familial Mediterranean fever (FMF) during attack and attack-free periods. METHODS: The study was conducted between June 2016 and January 2018. Clinical features and laboratory parameters of children with FMF during attack and attack-free periods were recorded longitudinally. RESULTS: The cohort consisted of 168 children with FMF (84 boys, 84 girls). Median values of acute phase reactants during FMF attacks were 433.5 mg/L (34.0-1780.0 mg/L) for serum amyloid A (SAA), 56.7 mg/L (7.6-379.0 mg/L) for C-reactive protein (CRP), and 37.5 mm/h (5-100 mm/h) for erythrocyte sedimentation rate (ESR). Median values for the same tests in attack-free periods were 3.2 mg/L (0.1-25.0 mg/L), 1.7 mg/L (0.1-12.7 mg/L), and 8 mm/h (1-30 mm/h), respectively. Correlation analyses showed that SAA and CRP were highly correlated in FMF attack (r = 0.67, p < 0.01), but no correlation was found between SAA and ESR levels. C-reactive protein was elevated in 13.6%, ESR in 20.8%, and SAA in 28.5% of the patients during attack-free period. Age at onset, sex of the patients, and characteristics of attacks were found to be not associated with elevated SAA in attack-free period. On the other hand, having homozygous exon 10 mutation and having elevated CRP were found to be associated with high SAA in attack-free period. CONCLUSIONS: C-reactive protein and SAA correlate well with FMF attacks. Therefore, checking for SAA during a FMF attack is not required. However, SAA seems to be the most sensitive method for demonstrating subclinical inflammation in attack-free period. Thus, checking SAA levels might be a valuable tool in selected FMF patients.

Age of onset as an influencing factor for disease severity in children with familial Mediterranean fever.

OBJECTIVES: To define the demographic, clinical and genetic features of familial Mediterranean fever (FMF) patients with early disease onset and to compare them with late-onset FMF patients. METHODS: Patients were divided into two groups according to the age of disease onset: group 1 includes the patients who had their first attack ≤3 years of age; group 2 consisted of patients who had their first attack >3 years of age. Furthermore, we compared the proportion of patients fulfilling the three diagnostic criteria among two groups. RESULTS: Of 1687 patients, 761 had first FMF attack at ≤3 years of age while 926 patients presented with their first manifestation of FMF at >3 years. Delay in diagnosis, fever and peritonitis were significantly higher in group 1. Frequency of arthritis, erysipelas-like erythema, non-nephrotic proteinuria, incomplete attacks, chronic arthritis, arthralgia and mean colchicine dose were significantly higher in group 2. Mean Pras score was higher and the presence of M694V mutation was more frequent in group 1. The percentage of children diagnosed according to Tel-Hashomer and pediatric criteria was significantly higher in group 1 than group 2. However, both groups meet Livneh criteria similarly. CONCLUSION: Although patients with early disease onset seem to have more severe disease course, they are more likely to have a delay in diagnosis. To avoid the diagnostic delay, clinicians should be aware of the findings of FMF in early age.

ADA2 Deficiency: Case Series of Five Patients with Varying Phenotypes.

OBJECTIVE: To describe the clinical features, genotype, and treatment approaches of patients with confirmed adenosine deaminase 2 (ADA2) deficiency with dissimilar phenotypes. METHODS: A case series of five DADA2 patients from three families was presented. The clinical and laboratory data, treatment protocols, and outcome of the patients were recorded from the patients' medical charts. ADA2 gene was screened by next generation sequencing first and then verified by Sanger sequencing. Serum ADA2 enzyme activity was measured by modified spectrophotometric method. RESULTS: The median (min-max) age at onset of symptoms and age at diagnosis were 11 (9-13.8) years and 15 (9-19) years, respectively. The median (min-max) follow-up period was 8 (6-45) months. There was consanguinity in two families (2/3). The main clinical manifestations are musculoskeletal (5/5), dermatological (4/5), and neurological (2/5). Homozygosity for the p.G47R mutation in ADA2 gene was detected in three patients. A homozygous mutation in ADA2 gene (c.650 T > A; p.Val217Asp) was detected in two siblings. Plasma ADA2 enzymatic activity was absent in all patients. Anti-tumor necrosis factor (TNF) therapy was commenced, and all patients became clinically inactive with normal acute-phase reactants. CONCLUSION: ADA2 mutations should be checked in patients with presence of inflammation and livedoid vasculitis when they have neurological findings, especially in the form of stroke; and a history suggesting for an inherited disease; or presence of resistance to conventional treatment. Besides, anti-TNF seems to be useful for treatment of DADA2.