Pyogenic sacroiliitis (PS) is one of the less frequent localizations among joint infections, near the 1,5%. A late diagnosis generally exists. So we decided to analyze its behaviour in our uniit. A retrospective study of 39 records was carried out, 32 with diagnosis of entrance of PS and 7 with another pathology's diagnosis that turned out to be a PS, among the years 1999 and 2014 in our unit. 27 only fulfilled the requirements to be classified as PS (Clinic features of infection and sacroiliac localization, laboratory exams and Tc-99 bone scintigraphy alterations). 20 males and 7 females (74% males), 52% right sacroiliac joint, only 7 had clinically predisposing conditions (trauma), aged between 3 and 14 years (average 9.6 years). The half time of clinical evolution foresaw to diagnosis was of 4,7 days (6,7 days between 1999–2005 and 3,5 between 2006–2014) (range between 1 and 10 days). The main symptom that motivates the consultation was fever (96%) accompanied by FABER test positive (70%) by buttock pain (52%) and by limping (48%). Laboratory exams: WBC count was normal in 11 cases and elevated in 16 cases too and only in 5 cases with left deviation (PMNs elevated); CRP higher than 55 mg/dl in 23 patients (100% over 20mg/dl), ERS with value average of 72 mmHg/hour (27–111). Blood cultures were positive in 70% and the Staphylococcus aureus was the main bacteria founded (89%). No radiological alterations were found initially. The TC-99 bone scintigraphy was positive in all cases after the third day. All patients had a 5 to 12 days course of intravenous antibiotics (oxacillin + amikacin in 96% of patients) and then completed 4 weeks with oral oxacillin. All patients recovered without sequel. Blood cultures may be obtained prior the antibiotics’ administration. The Staphylococcus aureus is by far the most frequent germ involved in this process, and it may guide the empiric antibiotic therapy. The precocious antibiotic treatment solves the case without sequels. The PS is an uncommon pathology in children that makes it often not recognized initially. Wrong diagnosis such as appendicitis, transient synovitis of the hip, discitis, etc. can be avoided if PS is sought in a systematic way.
