| Age of onset | 9 years | 6 years | 4 years |
| Attack duration | > 7 days | 4 - 5 days | 5 - 7 days |
| Interval between attacks | 6 - 12 weeks | 25 days | 1 month |
| Triggers | None | Upper respiratory tract infection | None |
| Cutaneous manifestations | Diffuse erythematous, warm plaque-like lesion of overlying skin of the calf | Painful ulcerated lesions in mouth (aphthous ulcers in oral mucosa) | None |
| Musculoskeletal manifestations | Severe calf pain | No arthritis | Monoarthritis of large joints (ankle, knee, elbow) in each episode: Non-deforming |
| Abdominal manifestations | None | None | None |
| Eye | None | Conjunctival congestion | None |
| Pleural, pericardial manifestations | None | None | Mild pericardial effusion + |
| Neurological manifestations | Meningeal signs + | None | None |
| Lymph/spleen | None | Bilateral cervical lymphadenopathy (level I & II, 2 X 1 cm); bilateral grade II tonsillar hypertrophy with congestion | Hepatosplenomegaly |
| Anthropometry and development | Normal as per age | Normal as per age | Normal as per age |
| Hematological investigations | Normocytic normochromic anemia; neutrophilic leukocytosis; raised inflammatory markers; CRP 160 mg/dL; ESR 60 mm in 1st hour | Normocytic normochromic anemia; neutrophilic leukocytosis; raised inflammatory markers; ESR- 39 mm in 1st hour; CRP- 98 mg/dL | Normocytic normochromic anemia; neutrophilic leukocytosis; raised inflammatory markers; CRP 185.9 mg/dL; ESR 55 mm in 1st hour |
| Infective workup | EBV, parvovirus B19, borrelia recurrentis, brucellosis, tuberculosis, histoplasmosis, leishmaniasis negative; blood culture sterile; urine culture sterile; CSF examination-8 lymphocytes, protein 60 mg%, glucose- normal, culture sterile | Tuberculosis negative; swab culture from oropharynx- no growth; blood culture- sterile | Brucella abortus antibody titers- reactive 1:80; Brucella melitensis antibody titers- reactive 1:320; Brucella DNA PCR- negative; EBV- negative; tuberculosis- negative; blood culture- sterile |
| Special test | ANA negative; ANCA negative; CECT head- normal; doppler of lower limb- normal; NCV- normal; muscle biopsy- monocytic fasciitis; immunodeficiency workup- negative | ANA negative; immnodeficiency workup- negative | Bone marrow biopsy is cellular, showing hematopoietic elements of all three lineages with normal maturation.no granuloma/atypical cells/hemoparasite seen; anti-CCP- negative; RA factor- negative; ANA – negative; DsDNA-negative; DCT-negative; immunodeficiency workup - negative |
| Genetic results | Negative for pathogenic variants of periodic fever genetic panel | Not done | Heterozygous missense variant in exon 10 of the MEFV gene |
| Diagnosis | Mutation negative tumor necrosis factor receptor- 1- associated periodic fever syndrome (TRAPS) like phenotype | PFAPA (periodic fever, aphthous stomatitis, pharyngitis, adenitis) | FMF |
| Treatment | Pulse steroid followed by maintenance steroid therapy; etanercept | Symptomatic management with NSAIDS and prednisolone 1 - 2 mg/kg single dose | Steroid; colchicine |
| Follow-up duration | 3 years; urinalysis- negative for micro albuminuria | 5 years | 2 years; urinalysis-negative for micro albuminuria |