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Introduction: A distinct strain of Klebsiella pneumoniae (K. pneumoniae) referred to as hypervirulent (hvKp) is associated with invasive infections such as pyogenic liver abscess in young and healthy individuals. In South Africa, limited information about the prevalence and virulence of this hvKp strain is available. The aim of this study was to determine the prevalence of hvKp and virulence-associated factors in K. pneumoniae isolates from one of the largest tertiary hospitals in a South African province. Methods: A total of 74 K. pneumoniae isolates were received from Pelonomi Tertiary Hospital National Health Laboratory Service (NHLS), Bloemfontein. Virulence-associated genes (rmpA, capsule serotype K1/K2, iroB and irp2) were screened using Polymerase Chain Reaction (PCR). The iutA (aerobactin transporter) gene was used as a primary biomarker of hvKp. The extracted DNAs were sequenced using the next-generation sequencing pipeline and the curated sequences were used for phylogeny analyses using appropriate bioinformatic tools. The virulence of hvKp vs. classical Klebsiella pneumoniae (cKp) was investigated using the Caenorhabditis elegans nematode model. Results: Nine (12.2%) isolates were identified as hvKp. Moreover, hvKp was significantly (p < 0.05) more virulent in vivo in Caenorhabditis elegans relative to cKp. The virulence-associated genes [rmpA, iroB, hypermucoviscous phenotype (hmv) phenotype and capsule K1/K2] were significantly (p < 0.05) associated with hvKp. A homology search of the curated sequences revealed a high percentage of identity between 99.8 and 100% with other homologous iutA gene sequences of other hvKp in the GenBank. Conclusion: Findings from this study confirm the presence of hvKp in a large tertiary hospital in central South Africa. However, the low prevalence and mild to moderate clinical presentation of infected patients suggest a marginal threat to public health. Further studies in different settings are required to establish the true potential impact of hvKp in developing countries.
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Background: The study aimed to calculate the predictive value of admission laboratory values in patients with perforated peptic ulcers. Methods: A retrospective, cohort analytical, observational study was performed, including patients with surgically confirmed perforated peptic ulcers over a 5-year period. Demographic data and admission laboratory values were collected from hospital electronic databases. Outcomes measured were in-hospital mortality, intensive care unit (ICU) admission and length of stay. The significance of categorical variables was calculated by chi-square and Fisher's exact test. Logistic regression analysis was performed to determine univariately statistically significant variables. Results: In total, 188 patients met the inclusion criteria. The median age was 46 (range 15-87) years with a male predominance of 71.3 % (n = 134). The median length of hospital stay was 7 (range 1-94) days and 31.4 % (n = 59) of patients were admitted to the ICU. Post-operative in-hospital mortality was 25.0 % (n = 47). Predicting the categorical outcome of in-hospital mortality, abnormal haemoglobin, platelet count, urea, creatinine and potassium levels were all found to be statistically significant in the univariate analysis. Age (odds ratio [OR] 1.03), haemoglobin (OR 4.36) and creatinine (OR 7.76) levels were significant in the multivariate analysis. Conclusions: Mortality rate among patients with perforated peptic ulcer disease is still substantial. Admission laboratory values showed statistical significance as outcome indicators and were valuable to assist in predicting the prognosis. An abnormally high serum creatinine level was the strongest single predictor of both mortality and ICU admission. Key message: Initial laboratory findings of patients admitted for perforated peptic ulcer showed that an abnormally high serum creatinine level was the strongest single predictor of both mortality and ICU admission.
