Tropical Medicine and Infectious Disease

Research

15 pages, 802 KiB

Open AccessArticle

Legionella pneumophila Presence in Dental Unit Waterlines: A Cultural and Molecular Investigation in the West Bank, Palestine

by Ashraf R. Zayed, Mutasem Burghal, Suha Butmeh, Ascel Samba-Louaka, Michael Steinert and Dina M. Bitar

Trop. Med. Infect. Dis. 2023, 8(11), 490; https://doi.org/10.3390/tropicalmed8110490 - 30 Oct 2023

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Abstract

A Legionella pneumophila bacterium is ubiquitous in water distribution systems, including dental unit waterlines (DUWLs). Legionellosis is atypical pneumonia, including Legionnaires’ disease (LD) and the less acute form of Pontiac fever. Legionellosis occurs as a result of inhalation/aspiration of aerosolized Legionella-contaminated water [...] Read more.

A Legionella pneumophila bacterium is ubiquitous in water distribution systems, including dental unit waterlines (DUWLs). Legionellosis is atypical pneumonia, including Legionnaires’ disease (LD) and the less acute form of Pontiac fever. Legionellosis occurs as a result of inhalation/aspiration of aerosolized Legionella-contaminated water by susceptible patients, health workers, and dentists. In this study, we undertook to determine the prevalence of Legionella in water and biofilm samples from Tap and DUWLs collected from five sites of dental clinics and faculties across the West Bank. Water samples were tested for physical and chemical parameters. The study samples included 185 samples, 89 (48%) water samples, and 96 (52%) biofilm swabs, which were analyzed by cultivation-dependent analysis (CDA) and by the cultivation-independent technique (CIA). Also, partial sequencing of the 16S rRNA gene for fifteen L. pneumophila isolates was performed for quality assurance and identification. L. pneumophila was isolated from 28 (15%) of 185 samples using CDA and was detected in 142 (77%) of 185 samples using CIA. The abundance of culturable L. pneumophila was low in DUWL of the sampling sites (range: 27–115 CFU/Liter). PCR was 5× more sensitive than the culture technique. L. pneumophila Sg 1 was detected in (75%) of the isolates, while (25%) isolates were L. pneumophila Sg 2–14. All fifteen sequenced Legionella isolates were identified as L. pneumophila ≥ 94.5%. The analysis of phylogenetic tree showed that L. pneumophila branch clearly identified and distinguished from other branches. These results show that DUWLs of the examined dental clinics and faculties are contaminated with L. pneumophila. This finding reveals a serious potential health risk for infection of immunocompromised patients and dentists’ post-exposure. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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10 pages, 421 KiB

Open AccessArticle

Community-Acquired, Bacteraemic Acinetobacter Baumannii Pneumonia: A Retrospective Review of Cases in Tropical Queensland, Australia

by Timothy Riddles and Daniel Judge

Trop. Med. Infect. Dis. 2023, 8(8), 419; https://doi.org/10.3390/tropicalmed8080419 - 18 Aug 2023

Cited by 3 | Viewed by 1258

Abstract

Background: Community-acquired Acinetobacter pneumonia (CAAP) typically presents with rapid progression to fulminant disease and is complicated by high mortality. Australian epidemiological studies are few. Methods: We conducted a retrospective study on bacteraemic cases of CAAP over twenty years (2000–2019) in North Queensland. Cases [...] Read more.

Background: Community-acquired Acinetobacter pneumonia (CAAP) typically presents with rapid progression to fulminant disease and is complicated by high mortality. Australian epidemiological studies are few. Methods: We conducted a retrospective study on bacteraemic cases of CAAP over twenty years (2000–2019) in North Queensland. Cases were selected on microbiologic, clinical, and radiographic parameters. Data on patient demographics were obtained, along with microbial, antibiotic, mortality and climatic data. Results: 28 cases of CAAP were included. Nineteen (67.9%) were male, twenty-three (82.1%) were Indigenous Australians, and the mean age was 45.9 years. Most presentations were of moderate to severe pneumonia (25/28 (89.3%)). Furthermore, 90% of cases had two or more risk factors. The strongest risk factors for CAAP were alcohol excess and tobacco use. No statistically significant difference in presenting severity, ICU admission or mortality was seen between dry- and wet-season disease. Dry-season disease accounted for 35.7% of cases. Overall mortality was 28.6%. Early use of meropenem or gentamicin reduced mortality irrespective of presenting severity (mortality 17.6%) Non-targeted antibiotic therapy was associated with a non-significant difference in mortality of 44.4%. Conclusions: Early administration of targeted antibiotics can mitigate a high mortality rate. The choice of antibiotic therapy for community-acquired pneumonia should be based on severity, risk factors and clinical suspicion of CAAP rather than seasonality. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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14 pages, 610 KiB

Open AccessEditor’s ChoiceArticle

Invasive Pneumococcal Disease in People Living with HIV: A Retrospective Case—Control Study in Brazil

by Roxana Flores Mamani, Tiago de Assunção López, Waldir Madany Jalo, Marcelo Ribeiro Alves, Estevão Portela Nunes, Mario Sérgio Pereira, Erica Aparecida dos Santos Ribeiro da Silva, Maria Cristina da Silva Lourenço, Valdiléa Gonçalves Veloso, Beatriz Jegerhorn Grinsztejn, Sandra Wagner Cardoso and Cristiane da Cruz Lamas

Trop. Med. Infect. Dis. 2023, 8(6), 328; https://doi.org/10.3390/tropicalmed8060328 - 19 Jun 2023

Viewed by 1700

Abstract

HIV-infected patients are at particular risk for invasive pneumococcal disease (IPD). We describe cases of IPD in people living with HIV/AIDS (PLWHA) and find associated risk factors for infection and death. Methods: A retrospective case-control study, nested in a cohort, including PLWHA with [...] Read more.

HIV-infected patients are at particular risk for invasive pneumococcal disease (IPD). We describe cases of IPD in people living with HIV/AIDS (PLWHA) and find associated risk factors for infection and death. Methods: A retrospective case-control study, nested in a cohort, including PLWHA with and without IPD, conducted in Brazil, 2005–2020. Controls were of the same gender/age and seen at the same time/place as cases. Results: We identified 55 episodes of IPD (cases) in 45 patients and 108 controls. The incidence of IPD was 964/100,000 person-years. A total of 42 of 55 (76.4%) IPD episodes presented with pneumonia and 11 (20%) with bacteremia without a focus and 38/45 (84.4%) were hospitalized. Blood cultures were positive in 54/55 (98.2%). Liver cirrhosis and COPD were the only factors associated with IPD in PLWHA in univariate analysis, although no associated factors were found in multivariate analysis. Penicillin resistance was found in 4/45 (8.9%). Regarding antiretroviral therapy (ART), 40/45 (88.9%) cases vs. 80/102 controls (74.1%) were in use (p = 0.07). Patients with HIV and IPD had a higher CD4 count of 267 cells/mm³ compared with the control group, in which it was 140 cells/mm³ (p = 0.027). Pneumococcal vaccination was documented in 19%. Alcoholism (p = 0.018), hepatic cirrhosis (p = 0.003), and lower nadir CD4 count (p = 0.033) were associated with the risk of death in patients with IPD. In-hospital mortality among PLWHA and IPD was 21.1%, and it was associated with thrombocytopenia and hypoalbuminemia, elevated band forms, creatinine, and aspartate aminotransferase (AST). Conclusions: The incidence of IPD in PLWHA remained high despite ART. The vaccination rate was low. Liver cirrhosis was associated with IPD and death. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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13 pages, 814 KiB

Open AccessArticle

Differences in Virulence Factors and Antimicrobial Susceptibility of Uropathogenic Enterococcus spp. Strains in a Rural Area of Uganda and a Spanish Secondary Hospital

by Félix Carrasco Calzada, John Jairo Aguilera, Jaime Esteban Moreno, Juan Cuadros González, David Roca Biosca, Laura Prieto-Pérez and Ramón Pérez-Tanoira

Trop. Med. Infect. Dis. 2023, 8(5), 282; https://doi.org/10.3390/tropicalmed8050282 - 16 May 2023

Cited by 1 | Viewed by 1637

Abstract

Enterococcus faecalis and Enterococcus faecium have become two of the most important agents of nosocomial diseases due to their constantly growing resistance. Enterococcal infections are associated with biofilms, which are intrinsically sensitive to antimicrobials. The main goal of this study was to compare [...] Read more.

Enterococcus faecalis and Enterococcus faecium have become two of the most important agents of nosocomial diseases due to their constantly growing resistance. Enterococcal infections are associated with biofilms, which are intrinsically sensitive to antimicrobials. The main goal of this study was to compare and relate their capacity to form biofilm and their antimicrobial sensitivity, as well as their virulence factors and their implicated genes, of strains isolated from patients with urinary tract infection (UTI) in a rural hospital in Uganda and a secondary hospital in Spain. A prospective study was conducted with 104 strains of E. faecalis and E. faecium isolated from patients with suspected UTI and who presented leukocyturia at the Saint Joseph Kitgum hospital (Uganda) and at the Hospital Universitario Principe de Asturias (Spain). All microorganisms were identified in Spain by MALDI-TOF mass spectrometry. Antimicrobial susceptibility studies were carried out using the Vitek^® 2 system (Biomériux, France). The biofilm formation capacity was studied by photospectrometry. Phenotypic and genotypic virulence factors were studied in all cases by PCR or expression techniques. In Uganda, we found a higher incidence of E. faecium (65.3%, n = 32), contrary to the situation found in Spain where most of the bacteria found belonged to E. faecalis (92.7%, n = 51). All E. faecalis strains were found to have very low levels of resistance to ampicillin, imipenem, and nitrofurantoin. However, E. faecium exhibited more than 25% resistance to these antibiotics. Although the esp gene has been shown in the results obtained to be an important initial agent in biofilm formation, we have also demonstrated in this study the intervention of other genes when esp is not present, such as the ace1 gene. No statistically significant relationships were found between the presence of agg and gelE genes and increased biofilm formation. The significant difference between the incidence of E. faecalis and E. faecium and biofilm formation, between samples from Spain and Uganda, shows us very different profiles between countries. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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12 pages, 7328 KiB

Open AccessArticle

Increased Prevalence of Symptomatic Human Intestinal Spirochetosis in MSM with High-Risk Sexual Behavior in a Cohort of 165 Individuals

by Ramón Pérez-Tanoira, Marta del Palacio Tamarit, Ana María Vicente Montaña, David Carmena, Pamela Köster, Miguel Górgolas, José R. Fortes Alen, Alfonso Cabello-Úbeda and Laura Prieto-Pérez

Trop. Med. Infect. Dis. 2023, 8(5), 250; https://doi.org/10.3390/tropicalmed8050250 - 26 Apr 2023

Cited by 2 | Viewed by 1425

Abstract

Human intestinal spirochetosis (HIS) can cause gastrointestinal symptoms, although asymptomatic infections have been described. Individuals from low-income countries, people living with HIV, and men who have sex with men (MSM) show increased risk. A retrospective review of all patients diagnosed with HIS (n [...] Read more.

Human intestinal spirochetosis (HIS) can cause gastrointestinal symptoms, although asymptomatic infections have been described. Individuals from low-income countries, people living with HIV, and men who have sex with men (MSM) show increased risk. A retrospective review of all patients diagnosed with HIS (n = 165) between January 2013 and October 2020 at a tertiary hospital in Madrid, Spain, was performed to assess risk factors for symptomatic HIS, symptoms, and response to treatment. Most patients were male (n = 156; 94.5%), 86.7% were MSM, and 23.5% practiced chemsex, of whom most were symptomatic (p = 0.039). Most patients (78.4%) reported unprotected oral-anal intercourse. A total of 124 (81.1%) were symptomatic; diarrhea was the most common complaint (68.3%). Multivariable regression showed increased odds of symptoms associated with age under 41 (odds ratio 5.44, 95% CI 1.87–15.88; p = 0.002). Colonoscopy was normal in 153 (92.7%). Furthermore, 66.7% presented previous or concomitant sexually transmitted diseases (STDs). Among the patients, 102 underwent testing for other gastrointestinal pathogens, with positive results in 20 (19.6%). All symptomatic patients without concomitant gastrointestinal infection presenting improvement on follow-up (42 of 53) had received either metronidazole or doxycycline (p = 0.049). HIS should be considered as a cause of chronic diarrhea in MSM with high-risk sexual behavior after other causes have been ruled out; treatment with metronidazole is recommended. Coinfection with other STDs is common. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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21 pages, 4693 KiB

Open AccessArticle

Development and Optimization of an Unbiased, Metagenomics-Based Pathogen Detection Workflow for Infectious Disease and Biosurveillance Applications

by Kyle Parker, Hillary Wood, Joseph A. Russell, David Yarmosh, Alan Shteyman, John Bagnoli, Brittany Knight, Jacob R. Aspinwall, Jonathan Jacobs, Kristine Werking and Richard Winegar

Trop. Med. Infect. Dis. 2023, 8(2), 121; https://doi.org/10.3390/tropicalmed8020121 - 15 Feb 2023

Cited by 5 | Viewed by 3489

Abstract

Rapid, specific, and sensitive identification of microbial pathogens is critical to infectious disease diagnosis and surveillance. Classical culture-based methods can be applied to a broad range of pathogens but have long turnaround times. Molecular methods, such as PCR, are time-effective but are not [...] Read more.

Rapid, specific, and sensitive identification of microbial pathogens is critical to infectious disease diagnosis and surveillance. Classical culture-based methods can be applied to a broad range of pathogens but have long turnaround times. Molecular methods, such as PCR, are time-effective but are not comprehensive and may not detect novel strains. Metagenomic shotgun next-generation sequencing (NGS) promises specific identification and characterization of any pathogen (viruses, bacteria, fungi, and protozoa) in a less biased way. Despite its great potential, NGS has yet to be widely adopted by clinical microbiology laboratories due in part to the absence of standardized workflows. Here, we describe a sample-to-answer workflow called PanGIA (Pan-Genomics for Infectious Agents) that includes simplified, standardized wet-lab procedures and data analysis with an easy-to-use bioinformatics tool. PanGIA is an end-to-end, multi-use workflow that can be used for pathogen detection and related applications, such as biosurveillance and biothreat detection. We performed a comprehensive survey and assessment of current, commercially available wet-lab technologies and open-source bioinformatics tools for each workflow component. The workflow includes total nucleic acid extraction from clinical human whole blood and environmental microbial forensic swabs as sample inputs, host nucleic acid depletion, dual DNA and RNA library preparation, shotgun sequencing on an Illumina MiSeq, and sequencing data analysis. The PanGIA workflow can be completed within 24 h and is currently compatible with bacteria and viruses. Here, we present data from the development and application of the clinical and environmental workflows, enabling the specific detection of pathogens associated with bloodstream infections and environmental biosurveillance, without the need for targeted assay development. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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Review

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19 pages, 5955 KiB

Open AccessReview

Atypical Skull-Base Osteomyelitis: Comprehensive Review and Multidisciplinary Management Viewpoints

by Jure Urbančič, Domen Vozel, Saba Battelino, Roman Bošnjak, Barbara Kokošar Ulčar, Tadeja Matos, Matic Munda, Lea Papst, Nejc Steiner, Matej Vouk and Nina Zidar

Trop. Med. Infect. Dis. 2023, 8(5), 254; https://doi.org/10.3390/tropicalmed8050254 - 28 Apr 2023

Cited by 2 | Viewed by 2982

Abstract

Atypical skull-base osteomyelitis is a rare but fatal disease that usually involves infection of the ethmoid, sphenoid, occipital, or temporal bones that form the skull base. Unlike typical (so-called otogenic), atypical skull-base osteomyelitis has no otogenic cause. Instead, some authors call atypical skull-base [...] Read more.

Atypical skull-base osteomyelitis is a rare but fatal disease that usually involves infection of the ethmoid, sphenoid, occipital, or temporal bones that form the skull base. Unlike typical (so-called otogenic), atypical skull-base osteomyelitis has no otogenic cause. Instead, some authors call atypical skull-base osteomyelitis sinonasal, since the infection most often originates from the nose and paranasal sinuses. Diagnosing and treating this disease is challenging. To assist in managing atypical skull-base osteomyelitis, a review of the most recent literature, with patient cases and multidisciplinary perspectives from otolaryngologists, neurosurgeons, radiologists, infectious disease specialists, pathologists, and clinical microbiologists, is provided in this paper. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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Other

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19 pages, 2883 KiB

Open AccessSystematic Review

Prevalence of Mutated Colistin-Resistant Klebsiella pneumoniae: A Systematic Review and Meta-Analysis

by Nik Yusnoraini Yusof, Nur Iffah Izzati Norazzman, Siti Nur’ain Warddah Ab Hakim, Mawaddah Mohd Azlan, Amy Amilda Anthony, Fatin Hamimi Mustafa, Naveed Ahmed, Ali A. Rabaan, Souad A. Almuthree, Abdulsalam Alawfi, Amer Alshengeti, Sara Alwarthan, Mohammed Garout, Eman Alawad and Chan Yean Yean

Trop. Med. Infect. Dis. 2022, 7(12), 414; https://doi.org/10.3390/tropicalmed7120414 - 02 Dec 2022

Cited by 9 | Viewed by 2453

Abstract

The emergence of genetic mutations in chromosomal genes and the transmissible plasmid-mediated colistin resistance gene may have helped in the spread of colistin resistance among various Klebsiella pneumoniae (K. pneumoniae) isolates and other different bacteria. In this study, the prevalence of [...] Read more.

The emergence of genetic mutations in chromosomal genes and the transmissible plasmid-mediated colistin resistance gene may have helped in the spread of colistin resistance among various Klebsiella pneumoniae (K. pneumoniae) isolates and other different bacteria. In this study, the prevalence of mutated colistin-resistant K. pneumoniae isolates was studied globally using a systematic review and meta-analysis approach. A systematic search was conducted in databases including PubMed, ScienceDirect, Scopus and Google Scholar. The pooled prevalence of mutated colistin resistance in K. pneumoniae isolates was analyzed using Comprehensive Meta-Analysis Software (CMA). A total of 50 articles were included in this study. The pooled prevalence of mutated colistin resistance in K. pneumoniae was estimated at 75.4% (95% CI = 67.2–82.1) at high heterogeneity (I² = 81.742%, p-value < 0.001). Meanwhile, the results of the subgroup analysis demonstrated the highest prevalence in Saudi Arabia with 97.9% (95% CI = 74.1–99.9%) and Egypt, with 4.5% (95% CI = 0.6–26.1%), had the lowest. The majority of mutations could be observed in the mgrB gene (88%), pmrB gene (54%) and phoQ gene (44%). The current study showed a high prevalence of the mutation of colistin resistance genes in K. pneumoniae. Therefore, it is recommended that regular monitoring be performed to control the spread of colistin resistance. Full article

(This article belongs to the Special Issue Clinically Relevant Bacterial Infections)

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