C Reactive Protein (CRP) and Infection

Hansen JG. Dahler-Eriksen BS.
Aalborg Sygehus, forskningsenheden for klinisk epidemiologi.
[C-reactive protein and infections in general practice]. [Review] [27 refs] [Danish]
Ugeskrift for Laeger. 162(17):2457-60, 2000 Apr 24.

Abstract
C-reactive protein (CRP) is a sensitive and non-specific inflammatory marker. The serum level of CRP starts to rise 6-12 hours after the start of an inflammatory stimulus. Sequential CRP measurements will have greater diagnostic value than a single measurement, and changes of the CRP values often reflect the clinical course. In use in general practice the diagnostic value of CRP is found to be high in adults with pneumonia, sinusitis and tonsillitis, however it is found to be low regarding otitis and pneumonia in children. As to urinary tract infections and salpingitis the value is still undefined. Measurement of CRP is an important diagnostic test but the analysis should not stand by itself but be evaluated together with the patient's history and clinical examination. [References: 27]

Chelsom J. Solberg CO
The Department of Medicine, Haukeland Hospital and University of Bergen, Norway.
Vertebral osteomyelitis at a Norwegian university hospital 1987-97: clinical features, laboratory findings and outcome.
Scandinavian Journal of Infectious Diseases. 30(2):147-51, 1998.

Abstract
Altogether 40 patients aged 13-91 y (average 58 y) with vertebral osteomyelitis were treated at the Bergen University Hospital between July 1987 and June 1997. All patients presented with back pain, 33 (83%) had vertebral tenderness, and 26 (65%) patients were febrile. The duration of symptoms before diagnosis was < 3 weeks in 13 patients, and from 3 to 16 weeks in the remaining 27 patients. C-reactive protein (CRP) level and erythrocyte sedimentation rate (ESR) were elevated in 39 and 38 patients, respectively. Staphylococcus aureus was the most frequent cause of osteomyelitis followed by Streptococcus spp., Escherichia coli and Mycobacterium tuberculosis. Magnetic resonance imaging was superior to other radiological methods and demonstrated changes consistent with osteomyelitis in all 23 patients examined with this method. 35 patients survived. 18/35 surviving patients had pareses and 17 underwent surgery with drainage of abscesses or laminectomy. All 35 patients made a good recovery and only 3 patients experienced permanent pareses. The diagnosis of vertebral osteomyelitis is easily missed, and treatment is often delayed, particularly in the elderly in whom signs of sepsis may not manifest. However, persisting localized pain and tenderness over the spine together with elevated CRP and ESR should prompt the physician to consider vertebral osteomyelitis. Fever and leukocytosis may support the diagnosis, but may not always be present.

Lala SG. Madhi SA. Pettifor JM.
Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa.
The discriminative value of C-reactive protein levels in distinguishing between community-acquired bacteraemic and respiratory virus-associated lower respiratory tract infections in HIV-1-infected and -uninfected children.
Annals of Tropical Paediatrics. 22(3):271-9, 2002 Sep.

Abstract
This study assessed the value of routine CRP measurements to discriminate between bacterial and viral lower respiratory tract infection (LRTI) in HIV-1-infected and -uninfected children. A total of 570 children, prospectively enrolled, were categorised into four aetiological groups, as follows: (i) bacteraemic pneumonia (n = 50), (ii) respiratory virus-associated LRTI (n = 146), (iii) bacteraemic and respiratory virus-associated (mixed) LRTI (n = 10), and (iv) LRTI of undetermined aetiology (n = 364). The discriminative ability of threshold CRP values was evaluated, and values predicting bacteraemic pneumonia were used to construct receiver-operating characteristic (ROC) plots. Median CRP values were significantly higher in bacteraemic pneumonia (195 mg/L, p < 0.0001), and threshold CRP values ranging from 10 to 100 mg/L differentiated bacteraemic from virus-associated LRTI (p < 0.0001). The discriminative ability of CRP values assessed by ROC plots in pneumonia is 80%, and CRP > or = 10 mg/L identified 90% of all bacteraemic pneumonia. In HIV-1 infection, median CRP values were significantly higher in bacteraemic pneumonia (200 mg/L) but correlated with levels in uninfected children, irrespective of LRTI aetiology. Although CRP responses are significantly different in bacteraemic and virus-associated LRTI, the considerable overlap between these aetiological groups hinders selection of threshold CRP values that are clinically useful in differentiating bacteraemic from virus-associated LRTI pneumonia.

MCengi M. Helji B. Rasi S. Dili M.
Institut za nefrologiju, Klinicki centar, Sarajevo, BiH.
[Role of C-reactive protein in systemic lupus erythematosus]. [Serbo-Croatian (Roman)]
edicinski Arhiv. 56(3):147-9, 2002.

Abstract
We prospectively estimated the CRP and erythrocyte sedimentation rate (ESR) level in the blood of patients with systemic lupus erythematosus (SLE), with aim to find the difference between relapse and infection, especially because the high fever is the same clinical sign for both. After following this problem, considering the relation between SLE and infection, we have found that: When SLE is active disease, the infection is common complication, Immunosuppressive therapy, particularly with steroids, prepares the conditions for infection, Infection and SLE are going together, and here is believe that infection is making the worsening of basic disease, A lot of SLE syndromes are differentiated with difficulties from syndromes caused from infection (pneumonia, arthritis, serositis). During 2 (two) years follow up of 10 patients suffering from SLE and fulfilled ARA criteria, we found 5 relapses and 3 infections, and all of them were followed and analyzed. We used the additional criteria for the estimation of the disease activity every patient separately. The CRP blood level was measured every month. According to a lot of clinicians, normal values of CRP are 0-0.5 mg/dl (0-5 mg/L) and ESR between 12-20 mm. Levels over 15 mg/L (1.5 mg/dl) are found with 4 SLE patients (5 SLE relapses), and 2 patients with infections (3 cases of infection). The median value of CRP in the course of infection was more than 60 mg/L, in comparison with SLE relapse (16.5 mg/L). All patients with SLE relapse had increased ESR level, but CRP wasn't, while with infection ESR and CRP were regularly increased in all cases. Measuring CRP in SLE is helpful in differentiating between infection and relapse, only under one condition: that serositis previously wasn't present.