The Negative Predictive Value of Absence of Fever in Excluding Septic Arthritis in Children
Date First Published:
May 27, 2008
Last Updated:
June 12, 2012
Report by:
Philip Morgan, ST3 Emergency Medicine (Leeds Teaching Hospitals NHS Trust)
Search checked by:
Jamie Cooper, Leeds Teaching Hospitals NHS Trust
Three-Part Question:
In [an afebrile child with an acutely painful joint not caused by trauma] Is [the absence of fever sufficient evidence] to [safely exclude the diagnosis of septic arthritis]
Clinical Scenario:
A 4 year old child present to the childrens area of the accident and emergency department with a painful tender hip joint. There is no history of trauma. His observations are normal and he has a temperature of 36.8C He has a normal xray and has has an ultrasound of the hip which shows a small effusion. He is awaiting blood tests. The mother feels blood tests are unnecessary. She asks you how necessary the blood tests are.
Search Strategy:
Medline search via PubMed
Systematic process of search and review.
Medline search terms accepted for title review if <200 matched items.
Title review;
removed duplicate items and eliminated irrelevant titles and those not in English
Abstract Review;
eliminated publications with the wrong outcome, patient group, and those reporting single cases or series of fewer than 10 cases
Full Text Review;
Attempt to extract outcome data
Systematic process of search and review.
Medline search terms accepted for title review if <200 matched items.
Title review;
removed duplicate items and eliminated irrelevant titles and those not in English
Abstract Review;
eliminated publications with the wrong outcome, patient group, and those reporting single cases or series of fewer than 10 cases
Full Text Review;
Attempt to extract outcome data
Search Details:
Septic Arthritist11808
"Septic Arthritis"t3017
"Septic Arthritis" childrent782
"Septic Arthritis" children temperaturet25 Included
"Septic Arthritis" paediatrict26 Included
"Septic Arthritis" pediatrict123 Included
pyarthrosis children t1858
pyarthrosis children temperature 30 Included
Systematic reviewing
Medline Searcht204t
Title reviewt18
Abstract Reviewt12
Paper reviewt8
"Septic Arthritis"t3017
"Septic Arthritis" childrent782
"Septic Arthritis" children temperaturet25 Included
"Septic Arthritis" paediatrict26 Included
"Septic Arthritis" pediatrict123 Included
pyarthrosis children t1858
pyarthrosis children temperature 30 Included
Systematic reviewing
Medline Searcht204t
Title reviewt18
Abstract Reviewt12
Paper reviewt8
Outcome:
Systematic searching
Medline Searcht204t
Title reviewtt18
Abstract Reviewt12
Paper reviewt8
Medline Searcht204t
Title reviewtt18
Abstract Reviewt12
Paper reviewt8
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Significance of Laboritory and Radiologic Findings for Differentiating Between Septic Arthritis and Transient Synovitis of the Hip Sung Taek Jung May-03 Korea | Children with a diagnosis of either Transient Synovitis or Septic Arthritis | Retrospective case control study comparing findings and results between 97 patients with transient synovitis and 27 with septic arthritis | Number of cases with Septic Arthritis and fever (temp <37.0C) | 21 out of 27 NPV no fever = 77.8% | Single centre Retrospective not prospective Case control therefore selection bias No subgroup analysis looking separately at neonates |
| Factors Distinguishing Septic Arthritis From Transient Synovitis of the Hip in Children a Prospective Study Michelle S. Caird Jun-06 USA | Children who underwent hip aspiration because of a suspicion of septic arthritis | Prospective case conrtol study collected data on 53 children of which 34 had septic arthritis | Number of patients with septic arthritis who had a fever (defined in this study as temperature >38.5) | 15 out of 34 NPV for temp <38.5 = 44% | Differing definition of fever to most studies Unclear as to criteria for diagnosis SA. States half confirmed half presumed. Only those who had hip aspiration included Small series Single centre |
| Clinical Signs and Laboritory Tests in the Differential diagnosis of Arthritis in Children Ilkka Kunnamo et al Jan-87 Finland | Children seen with a presenting complaint of arthritis in a childrens hospital having been first seen and referred by primary care doctors in an 18 month period starting in May 1982 | Uni and Multivatiate analysis was performed on various clinical and laboritory findings for a total of 7 diagnostic groups including Septic Arthritis | Number of Patients with Septic Arthritis who had a fever (defined in this study as temerature > 38.5C | 14 out of 18 NPV No fever = 77.8% | Small number of cases with Septic Arthritis Dated Retrospective |
| The painful hip: evaluation of criteria for clinical decision-making G F Eich et al Nov-99 Swizerland | Children presenting with irritable hip to Major University Childrens Hospital between 1988 and 1992 | Retrospective case control study of 89 cases of irritable hip using uni and multivariate analysis to differentiate between cases with Transient Synovitis, Septic Arthritis and Perthes. | Number of Patients with Septic Arthritis who had fever | 7 out of 8 NPV no fever 87.5% | Small number of patients with septic arthritis No definition of fever given Retrospective Case control suffers from selection bias Single centre |
| Sensetivity of Objective Parameters in Diagnosis of Pediatric Septic Hips David M. Klein 09/09/1996 USA | Children aged 0 - 6 with confirmed diagnoses of septic arthritis | Retrospective case control study of 26 children with septic arthritis | Number of patients with Septic Arthritis who had a temperature >37.0 | 21 out of 26 NPV normal temperature = 80.8% | Small series n = 26 Retrospective Case control studies limited by selection bias Single centre |
| Validation of a Clinical Prediction Rule for the Differentiation Between Septic Arthritis and Transient Synovitis of the hip in Children Mininder S Kocher Aug-04 USA | Children presenting to a Childrens' hospital with acutely irritable hip between 1997 and 2002 | Prospective case control study of 51 children with Septic Arthritis and 103 children with Transient Synovitis. The aim was to test the validity of a clinical prediction rule developed in the earlier paper by the same author. | Patients with Septic Arthritis with a | 23 out of 24 NPV no fever = 95.8% | "History of Fever" not defined clearly Same investigators validating their own scoring system invites accusation of bias |
| Differentiating Between Septic Arthritis and Transient Synovitis of the Hip in Children: An Evidence-Based Clinical Prediction Algorithm Mininder S Kocher Dec-99 USA | All children with acutely irritable hips seen at a major tertiary care children's hospital between 1979 and 1996 | Retrospective case control study. 282 cases of which 82 had a diagnosis of Septic Arthritis. 86 had Transient synovitis and 114 cases were excluded as being patients from atypical groups. The SA and TS groups were comparent on univariate and multivariate analysis with the purpose of drawing up a system for scoring the likelyhood of a diagnosis of SA | Patients with Septic Arthritis with a fever | 67 out of 82 NPV no fever | No clear definition of term "history of fever" Varying criteria used to diagnose SA Large number of patients excluded from analysis Retrospective Case control risks selection bias Single centre |
Author Commentary:
Quite a wide variety of results between investigators. Some studies differed in their definition of fever making direct comparison difficult.
The largest study had the highest number and proportion of patients with septic arthritis without fever. This study however defined fever at a quite high temperature (38.5C) and may have included patients with unproven Septic Arthritis in the Disease group.
Ignoring those issues the raw total number of patients with Septic Arthritis included in all the reviewed studies was 219 of which 168 had fever of some kind. This gives an overal negative predictive value of absence of fever of 76.7%
If you exclude the outlying study this rises to 82.7%
All the studies reviewed concluded that a combination of clinical findings, imaging and blood inflamatory markers were necessary to exclude septic arthritis.
The largest study had the highest number and proportion of patients with septic arthritis without fever. This study however defined fever at a quite high temperature (38.5C) and may have included patients with unproven Septic Arthritis in the Disease group.
Ignoring those issues the raw total number of patients with Septic Arthritis included in all the reviewed studies was 219 of which 168 had fever of some kind. This gives an overal negative predictive value of absence of fever of 76.7%
If you exclude the outlying study this rises to 82.7%
All the studies reviewed concluded that a combination of clinical findings, imaging and blood inflamatory markers were necessary to exclude septic arthritis.
Bottom Line:
Using lack of fever alone to exclude septic arthritis in children is by my calculations at best around 80% safe. Given the serious risks associated with the diagnosis of septic arthritis a panel of tests including inflamatory markers is necessary to avoid missing cases with disastrous results.
Level of Evidence:
Level 2: Studies considered were neither 1 or 3
References:
- Sung Taek Jung . Significance of Laboritory and Radiologic Findings for Differentiating Between Septic Arthritis and Transient Synovitis of the Hip
- Michelle S. Caird. Factors Distinguishing Septic Arthritis From Transient Synovitis of the Hip in Children a Prospective Study
- Ilkka Kunnamo et al. Clinical Signs and Laboritory Tests in the Differential diagnosis of Arthritis in Children
- G F Eich et al. The painful hip: evaluation of criteria for clinical decision-making
- David M. Klein. Sensetivity of Objective Parameters in Diagnosis of Pediatric Septic Hips
- Mininder S Kocher. Validation of a Clinical Prediction Rule for the Differentiation Between Septic Arthritis and Transient Synovitis of the hip in Children
- Mininder S Kocher. Differentiating Between Septic Arthritis and Transient Synovitis of the Hip in Children: An Evidence-Based Clinical Prediction Algorithm