Diagnostic usefulness of serum procalcitonin in patients with bacterial sepsis

Background

The Sequential Organ Failure Assessment (SOFA) score is used for the diagnosis of sepsis and involves clinical and laboratory parameters that may not be readily and/or timely available in most resource-poor settings. Procalcitonin (PCT) has its level changed in response to bacterial sepsis and its measurement costs only a fraction of the total cost of investigations required to calculate SOFA score. This study aims to determine the diagnostic usefulness of PCT in bacterial sepsis.

Materials and Methods

Ninety-nine participants were studied, divided into three groups: apparently healthy volunteers, those with bacterial infection without sepsis (SOFA score <2), and patients with bacterial sepsis (positive culture and SOFA ≥2). PCT level of each participant was measured and median group levels compared. Pearson's correlation was used to determine the correlation between serum PCT levels and SOFA scores in the sepsis group using a significance level of 5 percent (P < 0.05). Diagnostic usefulness of PCT was assessed using receiver operating characteristic (ROC).

Result

Positive correlation was found between serum PCT levels and SOFA scores among patients with sepsis r = 0.42, P = 0.016. At a concentration of ≥4.25 ng/ml, serum PCT as a surrogate for SOFA score had a sensitivity and specificity of 57.60% and 84.80%, respectively, for indicating sepsis. The area under the ROC curve (AUC) was 0.74 (95% CI {0.62 to 0.86}, P = 0.001).

Conclusion

Serum PCT concentration was significantly higher in bacterial sepsis compared to bacterial infection without sepsis and healthy state. PCT concentration demonstrated positive correlation with SOFA score in bacterial sepsis and can be used as surrogate for sepsis screening/monitoring in resource-poor settings.

Osmotic demyelination syndrome following acute kidney injury with hypernatremia

Osmotic demyelination syndrome (ODS) is a life-threatening neurological condition often associated with rapid correction of hyponatremia. While ODS is thought to be rare, with prevalence rates of not more than 0.5% in autopsy series, mortality rates are as high as 90% in some studies. Thus, timely diagnosis and life-saving treatment rest on a high index of suspicion among clinicians. In this report, we discuss the case and literature review of a 45-year-old female with sepsis, acute kidney injury, and spontaneous hypernatremia who developed ODS but responded to therapy with high dose steroids, antibiotics, and supportive care.

Should absolute lymphocyte count be used as a surrogate marker for CD4+ count in patients with HIV/AIDS?

The World Health Organization (WHO) has recommended the use of absolute lymphocyte count (ALC) as a potential marker for immunosuppression where CD4+ count is unavailable. However, there are conflicting reports on the usefulness of ALC as a surrogate marker for CD4+ counts in patients with HIV/AIDS, more so, in patients with HIV-associated tuberculosis (TB). To evaluate the usefulness of ALC as an alternative to CD4+ counts and to see whether TB affects the correlation of ALC with CD4+ counts in patients with HIV-associated TB. A total of 66 consecutive patients (33 with and 33 without TB) with a diagnosis of HIV infection were recruited into the study as cases. Another group of 66 subjects (33 subjects each) age- and sex-matched HIV-negative controls were recruited as controls and stratified in to two: a) HIV-negative PTB patients. b) apparently healthy HIV and PTB negative individuals. The age range was from 15-60 years (median: 32 years). The highest percentage (39%) of subjects fell in the age range of 25-29 years. The mean ALC for HIV-associated PTB was 3906 +/- 1092 cells/microl and for patients with HIV infection only. 4755 +/- 1049 cells/microl. There was no significant difference in mean ALC between males and females in both groups (P > 0.05). Patients with dual infection by M. tuberculosis and HIV had the lowest mean ALC (3906 +/- 1092 cells/microl). Healthy controls had mean ALC (+/- SD) of 5249 +/- 101 cells/microl. There was significant difference between the healthy controls and the other three groups. The observed difference was more in patients with HIV/ TB co-infection (P < 0.005) compared with patients with HIV alone (P < 0.05). No significant correlation was observed between CD4+ cell counts and ALC in all the age groups of the study population. When the CD4+ counts were divided into < 200 and > or = 200 cells/microl and the ALC into < 2000 and > or = 2000 cells/microl, the sensitivity, specificity and positive predictive values of the diagnostic usefulness of ALC in HIV-associated PTB were 52%. 56.3% and 78.8% while for HIV only patients the same values were 56.3%. 55.9% and 54.5%, respectively. We cannot recommend the use of ALC as a surrogate for CD4+ count in our environment as this study has clearly shown that the correlation between the two is weak. Patients with dual infection by HIV and M. tuberculosis are more likely to have lower CD4+ cell and AL counts than those with HIV infection occurring alone.