Differentiation of post-streptococcal reactive arthritis from acute rheumatic fever.
OBJECTIVE
To perform a retrospective study comparing clinical and laboratory aspects of patients with acute rheumatic fever (ARF) and patients with post-streptococcal reactive arthritis (PSRA), to discern whether these are 2 separate entities or varying clinical manifestations of the same disease.


METHODS
We located the records of 68 patients with ARF and 159 patients with PSRA, whose diseases were diagnosed with standardized criteria and treated by 8 pediatric rheumatologists in 7 medical centers, using the Israeli internet-based pediatric rheumatology registry. The medical records of these patients were reviewed for demographic, clinical, and laboratory variables, and the data were compared and analyzed with univariate, multivariate, and discriminatory analysis.


RESULTS
Four variables were found to differ significantly between ARF and PSRA and serve also as predictors: sedimentation rate, C-reactive protein, duration of joint symptoms after starting anti-inflammatory treatment, and relapse of joint symptoms after cessation of treatment. A discriminative equation was derived that enabled us to correctly classify >80% of the patients.


CONCLUSIONS
On the basis of simple clinical and laboratory variables, we were able to differentiate ARF from PSRA and correctly classify >80% of the patients. It appears that ARF and PSRA are distinct entities.
Barash
Judith
J
Pediatric Day Care and Pediatric Rheumatology Service, Kaplan Medical Center, Rehovot, Hebrew University, Jerusalem, Israel. judith_b@clalit.org.il
Mashiach
Eran
E
Navon-Elkan
Pnina
P
Berkun
Yackov
Y
Harel
Liora
L
Tauber
Tsivia
T
Padeh
Shai
S
Hashkes
Philip J
PJ
Uziel
Yosef
Y
D000208:Acute Disease; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D016918:Arthritis, Reactive / Q000175:diagnosis*; D002097:C-Reactive Protein / Q000378:metabolism; D003937:Diagnosis, Differential; D006801:Humans; D007557:Israel; D015999:Multivariate Analysis; D010372:Pediatrics / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012213:Rheumatic Fever / Q000175:diagnosis*; D012219:Rheumatology / Q000379:methods; D013290:Streptococcal Infections / Q000150:complications / Q000175:diagnosis*; D013297:Streptococcus pyogenes / Q000378:metabolism*
D000893:Anti-Inflammatory Agents; D002097:C-Reactive Protein