Author Affiliations: Division of Pediatric Medicine, Department of Pediatrics, The Hospital for Sick Children (Drs Berger and also Friedman), and Faculty of Medicine (Dr Saunders), University of Toronto; and Department of Biostatistics, Princess Margaret Hospital (Ms Wang), Toronto, Ontario, Canada.

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Objective To determine clinical and laboratory functions predictive of osteomyelitis in children with sickle cell disease and bony pain.

Design Patients in the situation team and also participants in the manage team were randomized in a 1:3 ratio.

Setting The Hospital for Sick Children, Toronto, Ontario, Canada.

Participants Patients via sickle cell disease and osteomyelitis (instance patients) and patients with sickle cell condition and also bony, vaso-occlusive crisis (regulate patients), 18 years or younger.

Main Outcome Measures Five qualities (number of painful sites, white blood cell count, swelling of the influenced limb, and duration of pain and fever before presentation) at the time of presentation to hospital.

Results File were analyzed for 31 cases and also 93 controls. Compared with controls, situations had actually more days of pain (5 vs 2 days; odds ratio , 1.2; 95% confidence interval , 1.1-1.4 days) and also fever (1 vs 0 day; 1.7; 1.2-2.4 days) prior to presentation. Cases were also even more most likely to have swelling of the affected limb(s) (71% vs 17%; OR, 11.8; 95% CI, 4.6%-30.0%) and fewer painful sites (1 vs 2; 0.7; 0.5-1.0). On laboratory testimonial, situations had better white blood cell counts (18.6 vs 15.6/μL; OR, 1.1; 95% CI, 1.0-1.1/μL). Multivariate logistic regression proved that the significant predictors of osteomyelitis were duration of fever (OR, 1.8; 95% CI, 1.2-2.6) and also pain (1.2; 1.0-1.4) before presentation and swelling of the influenced limb (8.4; 3.5-20.0). The risk of osteomyelitis was decreased if more than 1 painful site was existing (OR, 0.7; 95% CI, 0.5-1.0).

Conclusion In the clinical scenario of a son with sickle cell condition presenting via bony pain and also swelling affecting a single site, through expanded fever before and pain, the medical professional must take into consideration closer monitoring and also investigations to exclude a diagnosis of osteomyelitis.


Sickle cell condition (SCD) is the the majority of common single gene disorder in Afrideserve to Americans, affecting approximately 1 of 375 persons of Afrideserve to ancestry. Major complications of the disease in childhood include acute splenic sequestration crisis, aplastic crisis, acute chest syndrome, stroke, cholelithiasis, renal disease, infection, and also pain.1 A vaso-occlusive crisis (VOC) have the right to manifest as pain in the chest, abdomales, back, or limbs, emerging when the red blood cells sickle and also cause localized ischemia. Vaso-occlusive crisis affecting the bone is the many prevalent acute clinical manifestation of SCD in children.

Severe infections happen frequently as a result of impaired immune feature and useful asplenia, increasing the risk of bacterial sepsis and infection of the bone.2 Osteomyelitis can be an acute or a chronic inflammatory procedure of the bone caused by infection with pyogenic organisms. In children via SCD, the many prevalent organism responsible for osteomyelitis is non-Salmonella typhi, which has actually been reported to happen 2.2 times more often than Staphylococcus aureus.3 Diagnosing osteomyelitis in children via SCD have the right to be very tough. Children via osteomyelitis regularly current through fever and also a painful, swollen, tender limb through restricted variety of movement, indications and also symptoms that are equivalent to those discovered in patients via a VOC.

Tbelow is no definitive function on history, physical examination, laboratory test, or radiological research that can reliably differentiate between osteomyelitis and VOC, via the feasible exemption of a positive bacterial culture from the bone. However, a bone biopsy or aspiration is often not performed because it is an invasive procedure and also must be done prior to starting antibiotics to maximize the chance of obtaining a positive culture outcome. Additionally, bone cultures are reported to be positive in just 30% to 86% of instances,4 implying that tbelow is still a high false-negative rate. Cultures from the peripheral blood are also less specific in sustaining a diagnosis of osteomyelitis, and they are reported to show an organism in 30% to 76% of situations.4 Therefore, tright here are many cases in which no definitive diagnosis deserve to be made.

Many patients via SCD, in tandem through pain in the bone and fever before, are initially treated empirically for feasible osteoarticular infection or sepsis through broad-spectrum antibiotics. The antibiotics are discontinued at 48 hours if the blood society continues to be negative. However before, in instances in which the patient"s fever before and also pain are persistent despite negative blood, clinicians are frequently challenged through the dilemma of whether to treat for osteomyelitis. Faiattract to treat an unconfirmed case of osteomyelitis deserve to have significant aftermath, consisting of chronic bone damage, limb deformity, and sepsis.1 However before, unessential therapy for what is incorrectly thneed to be osteomyelitis have the right to have actually significant psychosocial, financial, and wellness care resource implications and also have the right to add to antibiotic resistance. Patients may additionally unnecessarily endure adverse impacts of the antibiotics and are at risk of complications from central intravenous lines that may be inserted to facilitate administration of antibiotics.

In a review of osteoarticular infections in children with SCD, 14 cases were determined during a 22-year duration.5 The predominant symptoms on presentation were pain, swelling, fever before, and tenderness. The large majority of patients had an elevated white blood cell (WBC) count and erythrocyte sedimentation rate. However before, this was a descriptive research through a tiny sample dimension and there was no comparison with patients through SCD having actually bony VOC.

Our goal in this research was to identify features on presentation that were predictive of osteomyelitis in youngsters via SCD. Based on a review of the literary works, our clinical endure, and also discussions through experts in this field, our hypothesis was that patients via SCD and osteomyelitis would certainly be more most likely to current with a much longer background of pain and also fever than would patients via VOC. In addition, we anticipated that patients via a solitary painful website, a greater WBC count, and also swelling of the influenced limb(s) would certainly be even more most likely to have osteomyelitis than to have actually VOC.


We perdeveloped a case-manage examine of patients through SCD, 18 years and also younger, that were admitted to The Hospital for Sick Children between January 1, 1988, and December 31, 2005. All participants were determined with usage of the hospital"s health and wellness records database. The examine was apshowed by the Research Ethics Board at The Hospital for Sick Children.

Cases were defined as patients through SCD who had a discharge diagnosis of osteomyelitis and also 1 or even more of the following criteria: (a) positive blood culture, (b) positive society of a bone or joint aspiprice, and/or (c) typical radiographic findings of osteomyelitis, as reported by a staff radiologist. Radiographic information included the findings from radiograph, bone shave the right to, ultrasound, magnetic resonance imaging, and gallium scan examinations. Patients through any kind of imaging findings that were reported by the radiologist as being “feasible osteomyelitis” or “osteomyelitis vs vaso-occlusive crisis,” and were therefore inconclusive, were not contained as situations of osteomyelitis. Only patients with radiographic imaging that was reported as “regular with osteomyelitis” or “typical of osteomyelitis” were coded as true situations. For instance, a patient with a radiographic report of “subperiosteal collection continual with osteomyelitis” would have been had as a instance.

Cases were excluded from the research if the patient was treated with antibiotics for much less than 2 consecutive weeks, because this would certainly suggest that the responsible doctor did not treat the patient as a true situation of osteomyelitis. Cases were additionally excluded if the patient had chronic osteomyelitis, rather than an acute presentation.

Control participants were patients through SCD who were admitted with a discharge diagnosis of VOC in the very same year as the case. Each potential control participant was assigned a code, which was gone into right into a random number generator (www.randomizer.org/develop.htm). For each situation had in the study, 3 randomly selected regulate participants were matched by year of admission.

For each situation and also manage, we taped the age of the patient on admission, the patient"s sex, and also the genoform of SCD. We accumulated data about the duration of pain and fever before prior to presentation and also the number of painful sites for each patient. The existence and also duration of fever before and also the duration of pain before presentation were based on the history provided by the parent or patient and recorded in the emergency department record or the admission note. If tbelow was a discrepancy between the admission note and the emergency department note, in that one documented fever or pain and the other did not, we offered the record that documented the information. We assumed that if this indevelopment was not documented, it was most likely that the question was not asked by the physician. If there was a discrepancy in the information, we sought corroborating proof elsewhere in the patient"s medical chart to clarify the issue. We also tape-recorded whether the doctor discovered swelling of the impacted limb on physical examination in the emergency department or at the moment of admission. If tbelow was no documentation about the visibility or absence of swelling, then this was coded as no swelling. The WBC count on the day of admission was taped directly from the laboratory documents.


Documents for situations and also matched controls were compared making use of the χ2 test or Fisher exact test for categorical variables and t test or the Mann-Whitney test for quantitative variables, as correct. Statistical analyses were carried out making use of SAS (version 9.1; SAS Institute Inc, Cary, North Carolina). Univariate analysis was percreated on candiday variables: duration of fever before prior to presentation, duration of pain prior to presentation, number of painful sites, presence of swelling, and WBC count. Variables with a value of P P

Tright here were a complete of 70 case patients through SCD that had actually a discharge diagnosis of osteomyelitis (Figure). Nineteen of these cases were excluded for having nonbony pain or chronic osteomyelitis. Of the staying 51 instances, 20 were excluded for not having a positive blood culture result, positive bone aspirate society, or typical radiographic imaging constant via osteomyelitis. Thirty-one situations met inclusion criteria. Documents were analyzed for these cases and also 93 matched controls through SCD and acute, bony VOC.


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Of the total 31 instances, 29 had actually findings on radiographic imaging that were tape-recorded by the radiologist as being regular via osteomyelitis. Two had abnormalities on imaging and neither had a bone biopsy percreated, however they both had actually positive blood culture. Many kind of of the cases had more than 1 imaging modality confirming their diagnosis. Nine cases were evidenced on magnetic resonance imaging, 13 on radiography, 8 on ultrasound, 1 on technetium bone sdeserve to, and 7 on gallium scan. Of the 29 cases through typical imaging for osteomyelitis, 9 additionally had actually positive blood or bone aspirate society, while the staying 20 had actually negative society.

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Tright here were no considerable distinctions between cases and controls in regards to age, sex, and also genokind of SCD (Table 1). Cases had a median of 5 days of pain before presentation, excluding the day of presentation (variety, 0-22 days), whereas controls had a median of just 2 days of pain (variety, 1-18 days; odds proportion , 1.2; 95% confidence interval , 1.1-1.4 days). Cases had actually a median of 1 day of fever before (array, 0-20 days), whereas controls reported no fever prior to the day of presentation (array, 0-4 days; OR, 1.7; 95% CI, 1.2-2.4 days). Seventy-one percent of instances compared with only 17% of controls presented via documented swelling of the impacted limb (OR, 11.8; 95% CI, 4.6%-30.0%). Cases had a median of just 1 painful website (variety, 0-6) compared with 2 sites of pain in controls (selection, 1-6; OR, 0.7; 95% CI, 0.5-1.0). On laboratory evaluation, participants had a 10% increase in the likelihood of having osteomyelitis for eexceptionally 1-U (1/μL) increase in the WBC count (95% CI, 1.0-1.1/μL) (Table 2).