Near-drowning-associated Aeromonas pneumonia

Microbial community profiling for forensic drowning diagnosis across locations and submersion times

BACKGROUND

Drowning diagnosis has long been a critical issue in forensic research, influenced by various factors such as the environment and decomposition time. While traditional methods such as diatom analysis have limitations in decomposed remains, microbial community profiling offers a promising alternative. With the advancement of high-throughput sequencing technology, forensic microbiology has become a prominent focus in the field, providing new research avenues for drowning diagnosis. During drowning, microbial communities enter the lung tissue along with the water.

METHODS

In this study, using a murine model, we collected samples from three rivers at random sites at postmortem intervals (PMI) of 1, 4, and 7 days‌ to comprehensively evaluate the differences in microbial communities between mice subjected to drowning versus postmortem immersion.

RESULTS

The α-diversity analysis revealed that the observed Operational Taxonomic Units (OTUs) for the drowning group on day 1 was 234.77 ± 16.60, significantly higher than the postmortem immersion group (171.32 ± 9.22), indicating greater initial microbial richness in the drowning group. Additionally, Shannon index analysis showed a significant decline in evenness in the postmortem immersion group on day 7 (1.46 ± 0.09), whereas the drowning group remained relatively stable (2.38 ± 0.15), further indicating a rapid decrease in microbial diversity in the postmortem immersion group over time. PCoA analysis demonstrated that differences in microbial community composition between drowning and postmortem immersion groups were notably stable. Key microbial taxa differentiating the groups were identified through LEfSe analysis, with Enterococcaceae (family), Escherichia-Shigella (genus), and Proteus (genus), emerging as significant markers in drowning cases. A random forest model, trained using microbial community data, exhibited high predictive accuracy (AUC = 0.96) across locations and immersion times and identified microbial markers, including Enterococcaceae (family), Lactobacillales (order), Morganellaceae (family), as critical features influencing model performance.

CONCLUSION

These findings underscore the potential of combining 16 S rRNA sequencing with machine learning as a powerful tool for drowning diagnosis, offering novel insights into forensic microbiology.

Fulminant fatal pneumonia and bacteremia due to Aeromonas dhakensis in an immunocompetent man: a case report and literature review

Background

Aeromonas dhakensis is associated with soft tissue infection, bacteremia and gastroenteritis. Involvement of respiratory system in adults is extremely rare. We report a case of fulminant pneumonia and bacteremia due to A. dhakensis in a patient without underlying diseases.

Case presentation

A 26-year-old man became ill suddenly with pneumonia after swimming in a river. Despite intensive support measures in the intensive care unit, he died 13 hours after admission and 4 days after his first symptoms. Autopsy showed abundant Gram-negative bacteria, massive inflammatory cell infiltration, edema, necrosis and hemorrhage in lung tissue. A. dhakensis was isolated from blood culture taken at admission and bronchoalveolar lavage fluid (BALF) after intubation. Moreover, A. dhakensis was also detected in lung tissue by metagenomic next-generation sequencing (mNGS) assay. The infection may have come from river water.

Conclusion

In patients who develop a fulminant pneumonia after contacting an aquatic environment, A. dhakensis should be alerted and mNGS may aid in the detection of aquatic pathogens by being more sensitive and specific versus traditional bacterial culture.

Clinical and microbiological features of drowning-associated pneumonia: a retrospective multicentre cohort study

OBJECTIVE

Pneumonia is the most frequent infectious complication in patients who have experienced drowning that requires intensive care unit (ICU) admission. We aimed to describe clinical, microbiological, and therapeutic data as well as predictors and impacts of such pneumonia on patients' outcomes.

METHODS

We conducted a retrospective, multicentre study (2013-2020) of 270 consecutive patients admitted for drowning to 14 ICUs in Western France. Their baseline characteristics and outcomes were compared according to the occurrence of drowning-associated pneumonia (DAP), defined as pneumonia diagnosed within 48 hours of ICU admission. A Cox regression model was used to compare survival on day 28, and logistic regression was used to identify risk factors for DAP. Microbiological characteristics and empirical antibacterial treatment were also analysed.

RESULTS

Among the 270 patients admitted to the ICU for drowning, 101 (37.4%) and 33 (12.2%) experienced pneumonia and microbiologically proven DAP, respectively. The occurrence of pneumonia was associated with higher severity scores at ICU admission (median Simplified Acute Physiology Score II, 34 [interquartile range {IQR}, 25-55] vs. 45 [IQR, 28-67]; p 0.006) and longer ICU length of stay (2 days [IQR, 1-3] vs. 4 days [IQR, 2-7]; p < 0.001). The 28-day mortality rate was higher among these patients (29/101 [28.7%] vs. 26/169 [15.4%]; p 0.013). Microbiologically proven DAP remained associated with higher 28-day mortality after adjustments for cardiac arrest and water salinity (adjusted hazard ratio, 1.86 [95% CI, 1.06-3.28]; p 0.03). A microbiological analysis of respiratory samples showed a high proportion of gram-negative bacilli (23/56; 41.1%), with a high prevalence of amoxicillin-clavulanate resistance (12/33; 36.4%).

CONCLUSIONS

Pneumonia is a common complication in patients admitted in the ICU for drowning and is associated with increased mortality.

Aeromonas and Human Health Disorders: Clinical Approaches

The genus Aeromonas comprises more than 30 Gram-negative bacterial species and naturally inhabitants from aquatic environments. These microorganisms, commonly regarded as pathogens of fish and several other animals, have been gaining prominence on medical trial due to its ability to colonize and infect human beings. Besides water, Aeromonas are widely spreaded on most varied sources like soil, vegetables, and food; Although its opportunistic nature, they are able to cause infections on immunocompromised or immunocompetent patients. Aeromonas species regarded as potential human pathogens are usually A. hydrophila, A. caviae, and A. veronii biovar sobria. The main clinical manifestations are gastrointestinal tract disorders, wound, and soft tissue infections, as well as septicemia. Regarding to antibiotic responses, the bacteria present a diversified susceptibility profile and show inherence resistance to ampicillin. Aeromonas, as an ascending genus in microbiology, has been carefully studied aiming comprehension and development of methods for detection and medical intervention of infectious processes, not fully elucidated in medicine. This review focuses on current clinical knowledge related to human health disorders caused by Aeromonas to contribute on development of efficient approaches able to recognize and impair the pathological processes.

Evaluation of Antimicrobial Utilization in the Pediatric Drowning Population

BACKGROUND

Management of pediatric drowning often includes evaluation and treatment of infectious disease. There are few data describing the infections associated with pediatric drowning.

METHODS

A descriptive retrospective study was designed, and patients aged < 19 years admitted for > 24 hours to our institution after a drowning were included from January 2011 through June 30, 2017. Data collection included patient demographics, submersion injury details, resuscitation details, patient admission details, chest radiograph on admission, use of intubation and mechanical ventilation, hospital length of stay, culture data, antimicrobial use, and mortality. Descriptive statistical methods (mean and standard deviation, median and range, percentage) were used to characterize the patient population, and Fisher exact test was used to evaluate the association between antimicrobial use in the first 72 hours of admission and mortality.

RESULTS

A total of 114 patients met study criteria (male, 59.7%; median age, 3.7 years [range, 0.15-17.79 years]). Median hospital length of stay was 2 days (range, 1-60 days). Intensive care unit admission occurred in 80.7%, intubation occurred in 46.5%, and mortality was 18.4%. The most common submersion location was a pool (76.3% [n = 87]) with water primarily characterized as freshwater (82.5% [n = 94]). Reported submersion time for the majority of patients was < 5 minutes (54.4%) with cardiopulmonary resuscitation in 78.1%. In the first 72 hours after admission, culture were obtained in 40 patients (35.1%), and 27.5% of these cultures were positive. The primary organisms identified were consistent oropharyngeal flora. Antimicrobials were initiated in 50% of the patient population with clindamycin as most common. There was not a significant association between antimicrobial use in the first 72 hours after admission and mortality (17.2% vs 19.6%, P = .81).

CONCLUSIONS

Infectious disease associated with pediatric drowning in pools is uncommon. Empiric use of antimicrobials does not appear to affect outcomes.

The Impact of Donor Asphyxiation or Drowning on Pediatric Lung Transplant Recipients

BACKGROUND

Donors with drowning or asphyxiation (DA) as a mechanism of death (MOD) are considered high risk in pediatric lung transplantation. We sought to evaluate whether recipients of DA donors had negatively impacted outcomes.

METHODS

Pediatric recipients recorded in the United Network for Organ Sharing registry between 2000 and 2019 were included. Primary stratification was donor MOD. Propensity matching with a 1:1 ratio was performed to balance the DA and non-DA MOD donor cohorts. Cox multivariable regression was used to determine the risk-adjusted impact of donor MOD. A subanalysis of the effect of lung allocation score was also evaluated.

RESULTS

A total of 1016 patients underwent bilateral lung transplantation during the study period, including 888 (85.6%) from non-DA donors and 128 (14.4%) from DA donors. Survival at 90 days, 1 year, and 2 years were similar in the matched and unmatched cohorts regardless of the donor MOD. Moreover, separate risk-adjusted analysis of drowning and asphyxiated donors was similar to other MOD donors at 30 days, 1 year, and 5 years. Similar survival findings persisted regardless of pretransplant lung allocation score. Although the rates of posttransplant stroke (1.0% versus 3.1%, P = 0.04) and the length of hospital stay (19 versus 22 d, P = 0.004) were elevated in the unmatched DA MOD recipients, these differences were mitigated after propensity matching.

CONCLUSIONS

This study evaluated the impact of DA MOD donors in pediatric lung transplant recipients and found similar rates of complications and survival in a propensity-matched cohort. These data collectively support the consideration of DA MOD donors for use in pediatric lung transplantation.

Bacteriological, Clinical and Virulence Aspects of Aeromonas-associated Diseases in Humans

Aeromonads have been isolated from varied environmental sources such as polluted and drinking water, as well as from tissues and body fluids of cold and warm-blooded animals. A phenotypically and genotypically heterogenous bacteria, aeromonads can be successfully identified by ribotyping and/or by analysing gyrB gene sequence, apart from classical biochemical characterization. Aeromonads are known to cause scepticemia in aquatic organisms, gastroenteritis and extraintestinal diseases such as scepticemia, skin, eye, wound and respiratory tract infections in humans. Several virulence and antibiotic resistance genes have been identified and isolated from this group, which if present in their mobile genetic elements, may be horizontally transferred to other naive environmental bacteria posing threat to the society. The extensive and indiscriminate use of antibiotics has given rise to many resistant varieties of bacteria. Multidrug resistance genes, such as NDM1, have been identified in this group of bacteria which is of serious health concern. Therefore, it is important to understand how antibiotic resistance develops and spreads in order to undertake preventive measures. It is also necessary to search and map putative virulence genes of Aeromonas for fighting the diseases caused by them. This review encompasses current knowledge of bacteriological, environmental, clinical and virulence aspects of the Aeromonas group and related diseases in humans and other animals of human concern.

[Near-drowning associated Aeromonas pneumonia]

INTRODUCTION

Aeromonas pneumonia associated with near-drowning, though uncommon, is serious and a major morbidity factor for patients.

CLINICAL CASE

A healthy 30-year-old man nearly drowned in a pound. He was admitted to the medical intensive care unit and required intubation and mechanical ventilation. He was given antibiotic therapy in the form of amoxicillin/clavulanic acid. After a brief stable period post immersion, he rapidly developed fever and respiratory failure. The thoracic scan revealed bilateral alveolar infiltrates and led to a fibreoptic bronchoscopy. Aeromonas veroniiandPseudomonas aeruginosa were found on culture of the bronchial aspirate. A change of antibiotic therapy appropriate to these bacteria led to clinical improvement and allowed complete withdrawal of ventilation.

CONCLUSION

Rapid respiratory deterioration following near-drowning should raise the suspicion of pulmonary infection with the bacteria usually found in the respiratory tract during ventilation but without overlooking the possibility of unusual organisms, particularly Aeromonas.It is usuallysensitive to third generation cephalosporins and fluoroquinolones. Ideally, Aeromonas should be sought in pulmonary aspirates and samples of the water where immersion occurred.

Nurses' Use of Global Information Systems for Provision of Outreach Reproductive Health Services to Internally Displaced Persons

Introduction:

A long and protracted civil war compounded by the occurrence of nature-related disasters have forced thousands of Somalis to take refuge in camps for internally displaced persons (IDPs) to escape violence and seek shelter. Dwellers of these camps have limited accessibility to and affordability of the fractured healthcare facilities located in nearby towns. A free, outreach, mobile, reproductive healthcare delivery system staffed with nurses and using an ambulance guided by a global information systems (GIS) map was established to address the accessibility and affordability issues hindering provision of quality reproductive healthcare to the women in the IDP camps and in the outskirts of Baidoa City, Somalia.

Methods:

All 14 IDP camps in Baidoa City were visited to determine the number of families/huts, and to acquire their global positioning system (GPS) central point locations. Global information systems (GIS) shape files containing major roads, river, and dwellings, and straight-line distances from the base clinic to each IDP camp were computed. The objective of creating and using this specially designed map was to help nurses in determining which camps realistically could be visited on a given day, and how best to access them considering the security situation and the condition of rain-affected areas in the city.

Results:

Use of the GIS map was instrumental in facilitating the delivery of healthcare services to IDPs and ensuring that resources were adequately utilized. Free healthcare services were provided each work day for the month long duration of the project; 3,095 consultations were provided, inclusive of 948 consultations for children under the age of 16 years, and delivery of three babies.

Conclusions:

Creation and use of a simple, need-specific GIS map in this pilot project effectively aided the logistical planning and delivery of mobile, outreach reproductive health services by directing the ambulance and nurses safely to accessible IDP camps in an area marred with long and protracted disasters from both natural and human causes.

Pneumonia caused by Aeromonas species in Taiwan, 2004-2011

We investigated the clinical characteristics of patients with pneumonia caused by Aeromonas species. Patients with pneumonia caused by Aeromonas species during the period 2004 to 2011 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed. Of the 84 patients with pneumonia due to Aeromonas species, possible Aeromonas pneumonia was diagnosed in 58 patients, probable Aeromonas pneumonia was diagnosed in 18 patients, and pneumonia due to Aeromonas was conclusively diagnosed in 8 patients. Most of the cases of Aeromonas pneumonia developed in men and in patients of advanced age. A. hydrophila (n = 50, 59.5 %) was the most common pathogen, followed by A. caviae (n = 24, 28.6 %), A. veronii biovar sobria (n = 7, 8.3 %), and A. veronii biovar veronii (n = 3, 3.6 %). Cancer (n = 37, 44.0 %) was the most common underlying disease, followed by diabetes mellitus (n = 27, 32.1 %). Drowning-associated pneumonia developed in 6 (7.1 %) patients. Of 47 patients who were admitted to the intensive care ward, 42 patients developed acute respiratory failure and 24 of those patients died. The overall in-hospital mortality rate was significantly associated with liver cirrhosis, cancer, initial presentation of shock, and usage of mechanical ventilation. In conclusion, Aeromonas species should be considered as one of the causative pathogens of severe pneumonia, especially in immunocompromised patients, and should be recognized as a cause of drowning-associated pneumonia. Cirrhosis, cancer, and shock as the initial presenting symptom are associated with poor outcome.

Detection of Aeromonas hydrophila in liquid media by volatile production similarity patterns, using a FF-2A electronic nose

A technique for rapid detection of pathogenic microorganisms is essential for the diagnosis of associated infections and for food safety analysis. Aeromonas hydrophila is one such food contaminant. Several methods for rapid detection of this pathogen have been developed; these include multiplex polymerase chain reaction assays and the colony overlay procedure for peptidases. However, these conventional methods can only be used to detect the microorganisms at high accuracy after symptomatic onset of the disease. Therefore, in the future, simple pre-screening methods may be useful for preventing food poisoning and disease. In this paper, we present a novel system for the rapid detection of the microorganism A. hydrophila in cultured media (in <2 h), with the use of an electronic nose (FF-2A). With this electronic nose, we detected the changes of volatile patterns produced by A. hydrophila after 30 min culture. Our calculations revealed that the increased volatiles were similar to the odours of organic acids and esters. In future, distinctive volatile production patterns of microorganisms identified with the electronic nose may have the potential in microorganism detection.

Selective culturing and genus-specific PCR detection for identification of Aeromonas in tissue samples to assist the medico-legal diagnosis of death by drowning

The detection of autochthonous aquatic bacteria in tissue samples from drowning cases is increasingly considered as an alternative approach to assist the medico-legal diagnosis of death by drowning. Bacteria belonging to the genus Aeromonas may be suitable candidates for this application as they are ubiquitous in natural aquatic environments but are generally not part of the human microbiota. The research aims of this study were (i) to develop a sensitive, specific and rapid screening and confirmation method for Aeromonas species in tissue samples and (ii) to evaluate aseptic sternal puncture as a post-mortem sample technique and bone marrow as an alternative matrix to provide evidence of death by drowning. The presence of Aeromonas in tissue samples was verified by cultivation using the selective media Ampicillin Dextrin Agar (ADA) and Ryan's Aeromonas Medium. The use of ADA medium was found most optimal for the sensitive, inexpensive and quick detection of aeromonads in human tissue samples. Positive culture plates were confirmed by harvesting all colonies for DNA extraction and subsequent PCR amplification using Aeromonas genus-specific primers. Aeromonads were detected in lung swab, blood and bone marrow of drowned bodies (n=3), but were negative in these three matrices for all negative controls (n=90) tested. Bone marrow proved to be a suitable alternative matrix and can be sampled post-mortem by an aseptic sternal puncture. In conclusion, this study confirms previous indications that aeromonads in cultures from blood of water bodies can be considered a potential marker for drowning. Given the fact that the number of immersed bodies (drowned and non-drowned) included in this study is statistically not significant, however, more tissue samples need to be investigated to confirm the validity of these methods to aid the diagnosis of death by wet drowning.

Pseudallescheria Boydii pneumonia in an immunocompetent host

Background:

Pseudallescheria boydii pneumonia is rarely reported among immunocompetent patients.

Case Report:

We report a case of a 62 year old white female with pseudallescheria boydii pneumonia. The patient was non-immunocompromised, had a history of mycobacterium avium complex (MAC) infection prior to presentation. After successful response to initial antitubercular therapy, the patient developed recurrent symptoms and bibasilar nodular infiltrates. Second line therapy for MAC failed to improve symptomatology. Pseudallescheria boydii pneumonia was diagnosed from a bronchoscopic biopsy. Treatment with voriconazole resolved her symptomatology and radiological infiltrates.

Conclusions:

This case highlights the importance of a high index of suspicion for superimposed fungal infections in patients who are refractory to medical treatment of bacterial pneumonitis such as MAC. Further diagnostic interventions are encouraged when insufficient clinical improvement is observed. Prompt initiation of an antifungal regimen is warranted.

Drowning associated pneumonia: a descriptive cohort

PURPOSE

Pneumonia is the most common infectious complication of drowning. Pneumonia is potentially life threatening and should be treated by effective antibiotic therapy. However the risk factors, microbiological causes, diagnostic approach and appropriate therapy for pneumonia associated with drowning are not well described. The microbiological ecology of the body of water where immersion occurred could be of import. The aim of this study was to report on microorganisms involved in pneumonia associated with drowning and out of hospital cardiac arrest after successful cardiopulmonary resuscitation. Additionally, we retrieved and undertook microbiological analysis on samples of water from our local river.

METHODS

This retrospective study included all patients having suffered an out of hospital cardiac arrest due to drowning and admitted to our tertiary care academic hospital between 2002 and 2010. Data concerning bacteriological lung samples (tracheal aspirate or bronchoalveolar lavage) at admission were reported and compared to bacteriological samples obtained from our local river (the river Seine).

RESULTS

A total of thirty-seven patients were included in the study. Lung samples were obtained for twenty-one of these patients. Lung samples were positive in nineteen cases, with a high frequency of multi-drug resistant bacteria. Samples from the Seine River found microorganisms similar to those found in drowning associated pneumonia.

CONCLUSIONS

Drowning associated pneumonia can be due to multi drug resistant bacteria. When treating drowning associated pneumonia, antibiotics should be effective against bacteria similar to those found in the body of water where immersion occurred.

Fulminant fatal bacteremic pneumonia due to Aeromonas hydrophila in a non-immunocompromised woman

A 75-year-old woman became ill suddenly with pneumonia two weeks after operation for colon cancer. Despite intensive support measures in the intensive care unit she died six hours after admission and 12 hours after her first symptom. Autopsy showed necrotizing pneumonia. Aeromonas hydrophila was isolated from a blood culture taken at admission and from the lung at autopsy. In patients who develop a fulminant disease of pneumonia, particularly those who have underlying medical conditions, Aeromonas hydrophila infection, though rare, should be considered.

Health impact of the 2004 Andaman Nicobar earthquake and tsunami in Indonesia

BACKGROUND

The human impact of the tsunami that occurred on 26 December 2004 was enormous, with Indonesia bearing a huge proportion of the losses. The aftermath brought predictions of communicable disease outbreaks and widespread fear of epidemics. However, evidence from previous disasters due to natural hazards does not support all of these predictions. The objectives of this study were to: (1) describe the relative importance of infectious diseases and injuries as a consequence of a disaster due to natural hazards; and (2) identify key recommendations for the improvement of control and surveillance of these diseases during and after disasters.

METHODS

A team from the Center for Research on the Epidemiology of Disasters visited Jakarta and Banda Aceh from 11-23 January 2005, and collected data from the Central and Provincial Ministries of Health (MOH), the World Health Organization (WHO), and a field hospital from the International Committee of the Red Cross in Banda Aceh. The epidemiological profiles of diseases before and after the tsunami were compared. Cholera, tetanus, wounds and wound infections, acute respiratory infections, malaria, and dengue were included in this analysis.

RESULTS

Certain diseases (e.g., cholera, malaria, dengue) are not always an immediate priority post-disaster. Rates of disaster-related health conditions requiring emergency response fell by half, and became negligible around four weeks after the precipitating events. Some conditions, such as aspiration pneumonia and tetanus, which normally are rare, require special preparedness for emergency personnel. In addition, resistant and rare pathogens are associated with disasters due to natural hazards in the tropics and require specialized knowledge for the rapid and successful treatment of related infections.

CONCLUSIONS

Within the first four weeks of a disaster, international humanitarian agencies in the health sector should start working with the MOH. The WHO surveillance system established immediately after the tsunami offers lessons for developing a prototype for future emergencies. Guidelines for tetanus and aspiration pneumonia should be included in disaster medicine handbooks, and humanitarian aid groups should be prepared to provide emergency obstetrics and post-natal services. Relief funding after naturally occurring disasters should consider funding sustainability. Donors should know when to stop providing emergency relief funds and transition to recovery/development strategies.

The genus Aeromonas: taxonomy, pathogenicity, and infection

Over the past decade, the genus Aeromonas has undergone a number of significant changes of practical importance to clinical microbiologists and scientists alike. In parallel with the molecular revolution in microbiology, several new species have been identified on a phylogenetic basis, and the genome of the type species, A. hydrophila ATCC 7966, has been sequenced. In addition to established disease associations, Aeromonas has been shown to be a significant cause of infections associated with natural disasters (hurricanes, tsunamis, and earthquakes) and has been linked to emerging or new illnesses, including near-drowning events, prostatitis, and hemolytic-uremic syndrome. Despite these achievements, issues still remain regarding the role that Aeromonas plays in bacterial gastroenteritis, the extent to which species identification should be attempted in the clinical laboratory, and laboratory reporting of test results from contaminated body sites containing aeromonads. This article provides an extensive review of these topics, in addition to others, such as taxonomic issues, microbial pathogenicity, and antimicrobial resistance markers.

One year ago not business as usual: wound management, infection and psychoemotional control during tertiary medical care following the 2004 Tsunami disaster in southeast Asia

Introduction

Following the 2004 tsunami disaster in southeast Asia severely injured tourists were repatriated via airlift to Germany. One cohort was triaged to the Cologne-Merheim Medical Center (Germany) for further medical care. We report on the tertiary medical care provided to this cohort of patients.

Methods

This study is an observational report on complex wound management, infection and psychoemotional control associated with the 2004 Tsunami disaster. The setting was an adult intensive care unit (ICU) of a level I trauma center and subjects included severely injured tsunami victims repatriated from the disaster area (19 to 68 years old; 10 females and 7 males with unknown co-morbidities).

Results

Multiple large flap lacerations (2 × 3 to 60 × 60 cm) at various body sites were characteristic. Lower extremities were mostly affected (88%), followed by upper extremities (29%), and head (18%). Two-thirds of patients presented with combined injuries to the thorax or fractures. Near-drowning involved the aspiration of immersion fluids, marine and soil debris into the respiratory tract and all patients displayed signs of pneumonitis and pneumonia upon arrival. Three patients presented with severe sinusitis. Microbiology identified a variety of common but also uncommon isolates that were often multi-resistant. Wound management included aggressive debridement together with vacuum-assisted closure in the interim between initial wound surgery and secondary closure. All patients received empiric anti-infective therapy using quinolones and clindamycin, later adapted to incoming results from microbiology and resistance patterns. This approach was effective in all but one patient who died due to severe fungal sepsis. All patients displayed severe signs of post-traumatic stress response.

Conclusion

Individuals evacuated to our facility sustained traumatic injuries to head, chest, and limbs that were often contaminated with highly resistant bacteria. Transferred patients from disaster areas should be isolated until their microbial flora is identified as they may introduce new pathogens into an ICU. Successful wound management, including aggressive debridement combined with vacuum-assisted closure was effective. Initial anti-infective therapy using quinolones combined with clindamycin was a good first-line choice. Psychoemotional intervention alleviated severe post-traumatic stress response. For optimum treatment and care a multidisciplinary approach is mandatory.

Infectious diseases of severe weather-related and flood-related natural disasters

PURPOSE OF REVIEW

The present review will focus on some of the possible infectious disease consequences of disastrous natural phenomena and severe weather, with a particular emphasis on infections associated with floods and the destruction of infrastructure.

RECENT FINDINGS

The risk of infectious diseases after weather or flood-related natural disasters is often specific to the event itself and is dependent on a number of factors, including the endemicity of specific pathogens in the affected region before the disaster, the type of disaster itself, the impact of the disaster on water and sanitation systems, the availability of shelter, the congregating of displaced persons, the functionality of the surviving public health infrastructure, the availability of healthcare services, and the rapidity, extent, and sustainability of the response after the disaster. Weather events and floods may also impact disease vectors and animal hosts in a complex system.

SUMMARY

Weather or flood-related natural disasters may be associated with an increased risk of soft tissue, respiratory, diarrheal, and vector-borne infectious diseases among survivors and responders.

Environmental insults: smoke inhalation, submersion, diving, and high altitude

In the expanding search for recreation, we spend more and more of our time in various environments. Whether the air is thin or compressed or smoke-filled or there is no air at all, emergency physicians continue to meet and treat the various pulmonary emergencies that the environment may create. The authors present the background, diagnosis, and management of a few of the more common pulmonary emergencies that the environment may produce.

Drowning

Recent epidemiologic data have shown that the burden of drowning is much greater than expected. Prevention and timely rescue are the most effective means of reducing the number of persons at risk. Early bystander cardiopulmonary resuscitation is the most important factor for survival after submersion. Cerebral damage is a serious threat when the hypoxic period is too long. In most situations, low body temperature is an indication of the severity of the drowning incident. Sometimes hypothermia that occurs during the submersion period can be brain protective. There is also new evidence to support the strategy of inducing mild hypothermia for a period of 12 to 24 hours in comatose drowning victims. In immersed patients, hypothermia should be treated. The most appropriate technique will depend on the available means in the hospital and the condition of the patient. Treatment of pulmonary complications depends on the lung injury that occurred during aspiration and the bacteria involved in aspiration. Understanding the pathophysiology of drowning may help us to understand lung injuries and ischemic brain injuries.

[Maturation pathway of hemolysin of Aeromonas sobria and the mechanism of action of the hemolysin]

Aeromonas sobria has been recognized as pathogens associated with acute gastroenteritis in both adults and children. The major virulence factor has been proposed to be hemolysin which possesses both hemolytic and enterotoxic activities. Mature (bio-active) hemolysin secreted out of cells binds to the target cells of the host and injure the cells. However, hemolysin remained in bacteria can not express such toxicity. It means that the maturation and secretion pathway of hemolysin is closely related to the pathogenicity of bacteria. Therefore, I examined the pathway and clarified the following events. Hemolysin synthesized in cytoplasm translocates across the inner membrane and appears in a periplasmic space. Hemolysins appeared in the space associates to form dimer in the space. The C-terminal region of hemolysin functions as a trigger in the association. Dimerized hemolysin crosses the outer membrane and emerges in milieu, but monomer can not cross it. Therefore, the C-terminal region of hemolysin attributes not only to the formation of the dimer but also to its secretion into milieu. Hemolysin emerged in milieu is inactive. Inactive hemolysin is converted to bio-Active hemolysin by deleting its carboxyl-terminal 42-amino-acid peptide. Active hemolysin generated binds to the receptor of the target cell and stimulates the production of cyclic AMP by the cell. I assume that this stimulation closely relates to the induction of diarrhea by hemolysin.

[Aeromonas spp bacteremia: study of 12 cases and review of the literature]

Twelve cases of Aeromonas spp. bacteremia are here reviewed in adult patients occurred at our institution during a 6-year period. Three cases corresponded to patients with hematological disease and four had a solid neoplasm. The source of infection in seven patients was extra-nosocomial; infections in the five remaining patients were considered to be acquired in the hospital. In seven patients, potential portals of entry were found. The usual clinical presentation was febrile syndrome in all cases and only in two patients did the clinical picture evolve to fulminant septic shock. Speciation of microorganisms was determined in only four cases: 2 A. hydrophilia, 1 A. caviae, and 1 A. veronii. Most isolates were susceptible to aminoglycosides, cotrimozazol, phosphomycin, and quinolonos, and resistant to ampicillin. Three patients (25%) died as a result of the infection. Aeromonas spp. bacteremia represented 0.12% of blood cultures in our hospital and occurs in immunosuppressed patients although it may be reported in previously healthy individuals.

Spontaneous bacterial empyema caused by Aeromonas veronii biotype sobria

Spontaneous bacterial empyema is a complication of hepatic hydrothorax in cirrhotic patients. The pathogen, clinical course and treatment strategy are different to the empyema secondary to pneumonia. A 54-year-old man, who was a cirrhotic patient with hepatic hydrothorax, was admitted to National Taiwan University Hospital for fever, dyspnea and right side pleuritic pain. The image study revealed massive right pleural effusion and no evidence of pneumonia. The culture of pleural effusion yielded Aeromonas veronii biotype sobria. The diagnosis of spontaneous bacterial empyema caused by Aeromonas veronii biotype sobria was established. To our best knowledge, Aeromonas veronii biotype sobria had never been reported in English literature as the causative pathogen of spontaneous bacterial empyema.

Near-drowning: life-saving steps

Cervical-spine injury, trauma, and hypothermia should be considered in all sports-related near-drownings. The focus of resuscitation should be on prompt restoration of respiration, CPR, and advanced cardiac life support with cervical-spine precautions. A subset of near-drowning victims can be discharged after only 4 to 6 hours of observation. Although total drowning deaths have decreased 45% in the past 15 years, a greater emphasis on public education to prevent drowning remains in order.