Dataset Information

Pneumococcal colonisation density: a new marker for disease severity in HIV-infected adults with pneumonia.

ABSTRACT:

Objective

A high genomic load of Pneumococcus from blood or cerebrospinal fluid has been associated with increased mortality. We aimed to analyse whether nasopharyngeal colonisation density in HIV-infected patients with community-acquired pneumonia (CAP) is associated with markers of disease severity or poor outcome.

Methods

Quantitative lytA real-time PCR was performed on nasopharyngeal swabs in HIV-infected South African adults hospitalised for acute CAP at Chris Hani Baragwanath Hospital, Soweto, South Africa. Pneumonia aetiology was considered pneumococcal if any sputum culture or Gram stain, urinary pneumococcal C-polysaccharide-based antigen, blood culture or whole blood lytA real-time PCR revealed pneumococci.

Results

There was a moderate correlation between the mean nasopharyngeal colonisation densities and increasing CURB65 scores among all-cause patients with pneumonia (Spearman correlation coefficient r=0.15, p=0.06) or with the Pitt bacteraemia score among patients with pneumococcal bacteraemia (p=0.63). In patients with pneumococcal pneumonia, nasopharyngeal pneumococcal colonisation density was higher among non-survivors than survivors (7.7 vs 6.1 log10 copies/mL, respectively, p=0.02) and among those who had pneumococci identified from blood cultures and/or by whole blood lytA real-time PCR than those with non-bacteraemic pneumococcal pneumonia (6.6 vs 5.6 log10 copies/mL, p=0.03). Nasopharyngeal colonisation density correlated positively with the biomarkers procalcitonin (Spearman correlation coefficient r=0.37, p<0.0001), proadrenomedullin (r=0.39, p=0.008) and copeptin (r=0.30, p=0.01).

Conclusions

In addition to its previously reported role as a diagnostic tool for pneumococcal pneumonia, quantitative nasopharyngeal colonisation density also correlates with mortality and prognostic biomarkers. It may also be useful as a severity marker for pneumococcal pneumonia in HIV-infected adults.

SUBMITTER: Albrich WC

PROVIDER: S-EPMC4127937 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BACKGROUND:Streptococcus pneumoniae is a leading and serious coinfection in adults with human immunodeficiency virus (HIV) infection, particularly in Africa. Prevention of this disease by vaccination with the current 23-valent polysaccharide vaccine is suboptimal. Protein conjugate vaccines offer a further option for protection, but data on their clinical efficacy in adults are needed. METHODS:In this double-blind, randomized, placebo-controlled clinical efficacy trial, we studied the efficacy of a 7-valent conjugate pneumococcal vaccine in predominantly HIV-infected Malawian adolescents and adults who had recovered from documented invasive pneumococcal disease. Two doses of vaccine were given 4 weeks apart. The primary end point was a further episode of pneumococcal infection caused by vaccine serotypes or serotype 6A. RESULTS:From February 2003 through October 2007, we followed 496 patients (of whom 44% were male and 88% were HIV-seropositive) for 798 person-years of observation. There were 67 episodes of pneumococcal disease in 52 patients, all in the HIV-infected subgroup. In 24 patients, there were 19 episodes that were caused by vaccine serotypes and 5 episodes that were caused by the 6A serotype. Of these episodes, 5 occurred in the vaccine group and 19 in the placebo group, for a vaccine efficacy of 74% (95% confidence interval [CI], 30 to 90). There were 73 deaths from any cause in the vaccine group and 63 in the placebo group (hazard ratio in the vaccine group, 1.18; 95% CI, 0.84 to 1.66). The number of serious adverse events within 14 days after vaccination was significantly lower in the vaccine group than in the placebo group (3 vs. 17, P=0.002), and the number of minor adverse events was significantly higher in the vaccine group (41 vs. 13, P=0.003). CONCLUSIONS:The 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine serotypes or serotype 6A. (Current Controlled Trials number, ISRCTN54494731.)

Project description:BackgroundHyponatremia is a frequent electrolyte disorder in HIV-infected patients with a prevalence of up to 56% in the pre-cART era. Several studies have demonstrated that patients with hyponatremia are at an increased risk of death. We aimed to investigate the prevalence of hyponatremia in the recent cART-era and evaluate its association with mortality.MethodsSingle-center retrospective cohort study. A total of 1196 newly diagnosed and cART-naïve HIV patients followed at the AIDS Reference Center, St Pierre University Hospital in Brussels, Belgium, between 1 January 1998 and 31 December 2013 were included. Hyponatremia was defined as a baseline natremia lower than 135 mmol/l. The outcome of interest was the occurrence of death.ResultsIn this study 177 (14.8%) patients had hyponatremia at baseline with a median natremia of 132.0 mmol/l [interquartile range (IQR) 130.0-134.0 mmol/l]. Hyponatremic patients had a lower CD4 cell count (207.5 ± 197.7/μl vs 400.4 ± 277.0/μl; P < 0.0001) and a higher prevalence of AIDS (50.3% vs 12.4%; P < 0.0001) compared to normonatremic patients. A significantly higher proportion of patients with hyponatremia were hospitalized at first contact (72.3% vs 20.0%; P < 0.0001). During the follow-up hyponatremic patients had a shorter median time to a first hospitalization (2.0 IQR [0.0-12.0] months vs 13.0 IQR [2.0-29.0] months; P = 0.001) and an increased incident hospitalization rate (785/1000 patient-years, 95% CI 725-845 vs 370/1000 patient-years, 95% CI 352-388; P < 0.0001]. The incident mortality rate was 28.3/1000 patient-years (95% CI 18.15-42.16) in patients with hyponatremia compared to 9.33/1000 patient-years (95% CI 6.63-12.75) in normonatremic patients (P < 0.0001). Three-year cumulative survival rates were 85.8% ± 3.0% in hyponatremic patients and 96.3% ± 0.7% in normonatremic patients (log-rank P < 0.0001). However, in a multivariate Cox model adjusting for other risk factors such as AIDS, CD4 count < 350/μl and hepatitis C, hyponatremia was no longer a predictor for patient death (hazard ratio: 1.03, 95% CI 0.54-1.97; P = 0.935).ConclusionsHyponatremia is a marker of severity of HIV-disease but not an independent risk factor for mortality. HIV-patients with a low serum sodium at baseline might benefit from a close follow-up to improve outcomes.