Differentiating PFAPA syndrome from monogenic periodic fevers.
OBJECTIVE
To analyze whether there were clinical differences between genetically positive and negative patients fulfilling periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome criteria and to test the accuracy of the Gaslini diagnostic score for identifying patients with PFAPA syndrome with higher probabilities of carrying relevant mutations in genes associated with periodic fevers.


METHODS
Complete clinical and genetic information was available for 393 children with periodic fever; 82 had positive genetic test results, 75 had incomplete genetic test results, and 236 had negative results for MVK, TNFRSF1A, and MEFV mutations. Current diagnostic criteria for PFAPA syndrome were applied.


RESULTS
Of 393 children, 210 satisfied PFAPA syndrome criteria; 43 carried diagnostic mutations (mevalonate kinase deficiency: n = 33; tumor necrosis factor receptor-associated periodic syndrome: n = 3; familial Mediterranean fever: n = 7), 37 displayed low-penetrance mutations or incomplete genotypes, and 130 demonstrated negative genetic testing results. Genetically positive patients had higher frequencies of abdominal pain and diarrhea (P < .001), vomiting (P = .006), and cutaneous rash and arthralgia (P = .01). Genetically negative patients had a higher frequency of exudative pharyngitis (P = .010). Genetically undetermined patients showed the same pattern of symptom frequency as genetically negative patients. The Gaslini diagnostic score was able to identify 91% of genetically positive patients correctly, with a global accuracy of 66%.


CONCLUSIONS
The Gaslini diagnostic score represents a useful tool to identify patients meeting PFAPA syndrome criteria and at low risk of carrying relevant mutations in genes associated with periodic fevers.
UO Pediatria II, G. Gaslini Institute, Largo G. Gaslini 5, 16146, Genova, Italy. marcogattorno@ospedale-gaslini.ge.it
Marco
M
Gattorno
Roberta
R
Caorsi
Antonella
A
Meini
Marco
M
Cattalini
Silvia
S
Federici
Francesco
F
Zulian
Elisabetta
E
Cortis
Giuseppina
G
Calcagno
Alberto
A
Tommasini
Rita
R
Consolini
Gabriele
G
Simonini
Maria Antonietta
MA
Pelagatti
Maurizia
M
Baldi
Isabella
I
Ceccherini
Alessandro
A
Plebani
Joost
J
Frenkel
Maria Pia
MP
Sormani
Alberto
A
Martini
D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003937:Diagnosis, Differential; D010505:Familial Mediterranean Fever / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D005335:Fever of Unknown Origin / Q000175:diagnosis / Q000235:genetics; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D006801:Humans; D008199:Lymphadenitis / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D009154:Mutation; D010612:Pharyngitis / Q000175:diagnosis / Q000235:genetics*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics; D018124:Receptors, Tumor Necrosis Factor / Q000235:genetics; D013281:Stomatitis, Aphthous / Q000175:diagnosis / Q000235:genetics*; D013577:Syndrome
D018124:Receptors, Tumor Necrosis Factor; D017853:Phosphotransferases (Alcohol Group Acceptor); C021796:mevalonate kinase