Aeromonas hydrophilia infections after penetrating foot trauma

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.

Bone graft donor site infection with a rare organism, Aeromonas Hydrophila. A typical location, presentation and organism with 2 years follow-up. Case report

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A. Hydrophila found in immunocompromised patients, burns or aquatic trauma patients.

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Aeromonas produce β-lactamase making it resistant to usual prophylactic antibiotics.

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Early surgical and antibiotic treatment is essential.

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Following a multidisciplinary approach, these patients avoid catastrophic results.

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Combined case report with detailed review of A. Hydrophila from recent literature.

Introduction

Aeromonas are Gram-negative bacilli often causing necrotizing fasciitis or sepsis in immunocompromised patients. Aeromonas Hydrophila is most often found in immunocompromised patients or those with burns or aquatic trauma. When patients present with a discharge and infection on bone graft donor site and progressive sepsis, an Aeromonas hydrophila infection should be considered in the differential diagnosis.

Presentation of case

We report here a rare case of Aeromonas hydrophila with surgical site sepsis/infection in an immunocompromised 69 years old female, with several comorbids. Here we are reporting infection on donor surgical graft site, sparing major surgical site with the implant. After getting culture report of exudates from the wound that grew A. hydrophila, immediate wound debridement and antibiotic beads insertion was performed with appropriate antimicrobial therapy and regular wound dressing. She was followed for around 2 years.

Discussion

This is the first report to our knowledge of A. Hydrophila infection in bone graft donor site. Aeromonas most often cause gastrointestinal and soft tissue infections, and bacteremia in immunocompromised patients. Early surgical intervention is essential to reducing mortality in deep soft tissue infections caused by this organism. Aeromonas have shown resistance to penicillin but are sensitive to other broad-spectrum antibiotics.

Conclusion

Early suspicion, diagnosis, and treatment with potent antibiotics are needed to prevent any further complications resulting from infection by this emerging aggressive pathogen.

Multifocal Aeromonas Osteomyelitis in a Child with Leukemia

Aeromonas hydrophila is a Gram negative organism causing both intestinal and extraintestinal disease. The case of a 14-year-old girl with underlying immunodeficiency and leukemia who developed systemic A. hydrophila infection is described in this report. While in deep bone marrow aplasia she developed fever, severe pain in the lower extremities, and swelling of the left femur. Blood culture showed Escherichia coli and A. hydrophila whereas pus culture from the soft tissue swelling showed the presence of A. hydrophila. Imaging studies showed diffuse osteolytic lesions. Patient received 5 months of intravenous and oral antibiotics and she improved clinically whereas the radiology findings persisted.

Achilles tendon infection due to Mycobacterium chelonae

Atypical tuberculous tenosynovitis of the foot and ankle is extremely rare. The determination of the Mycobacterium species is essential because resistance of atypical mycobacterial strains to antituberculous drugs is often encountered. We report a case of Mycobacterium chelonae paratendinous and intratendinous infection involving the Achilles tendon. Repeat aggressive irrigation and debridement procedures, coupled with removal of foreign materials and the appropriate use of prolonged antibiotic therapy, can result in a successful long-term outcome.

Enterobacter asburiae and Aeromonas hydrophila: soft tissue infection requiring debridement

Enterobacter asburiae and Aeromonas hydrophila are gram-negative bacilli that have been isolated in soil and water. Enterobacter asburiae can cause an array of diseases, and exposure to A hydrophila can cause soft tissue infections, including necrotizing faciitis.A healthy-appearing 22-year-old man presented with an innocuous soft tissue injury to his leg due to an all-terrain vehicle crash. He received intravenous antibiotics and was discharged with prophylactic oral antibiotics. After the rapid onset of high fevers (102°F-103°F) <24 hours postinjury, he returned to the emergency department. Emergent surgical debridement was performed, and broad-spectrum intravenous antibiotics were started. Fevers persisted, and the patient underwent repeat extensive surgical debridement and antibiotic bead placement <30 hours after the initial surgical debridement and broad-spectrum antibiotics. Intraoperative cultures found E asburiae and A hydrophila in the wound. Following a long course of antibiotics and a skin graft, he fully recovered and had no functional deficits 1 year postoperatively.Extensive research revealed that these organisms are rare in soft tissue infections. E asburiae is opportunistic but has not been reported as a primary wound organism, and A hydrophila infections have been reported following motor vehicle crashes involving wound contamination. At presentation, it is challenging to determine rare organisms in a timely fashion; however, emergent extensive surgical intervention of an accelerated aberrant disease process should be considered to avoid catastrophic outcomes.

Post-traumatic skin and soft tissue infection due to Aeromonas hydrophila

We report a case of posttraumatic skin and soft tissue infection in a patient who sustained laceration after being hit by a water tanker. Aeromonas hydrophila was isolated from pus and was identified to the species level by Vitek 2 and a battery of biochemical tests. The patient responded to thorough drainage, debridement of wound and 2 weeks of intravenous antibiotics. The patient was taken up for split skin grafting of the raw area. She was discharged with satisfactory graft uptake after 1 week without any further antibiotics advice. Follow-up after 3 weeks was satisfactory with healthy cover on the raw area and normal weight bearing on the left leg.

Necrotizing Fasciitis Caused by Inconspicuous Infection of Aeromonas hydrophila in an Immunocompromised Host

We present a case of serious necrotizing fasciitis due to Aeromonas hydrophila without a suggestive history of routes of pathogen invasion in a 60-year-old male. Despite prompt broad-spectrum antibiotic and extensive surgical therapies, the patient died within 72 hours following initial presentation. Our experience suggests clinicians be highly alert to the disease when an immunocompromised patient featured fulminant soft-tissue infection in the endemic area.

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.

Case reports: fatal necrotizing fasciitis caused by Aeromonas sobria in two diabetic patients

We report two rare cases of Aeromonas sobria necrotizing fasciitis with sepsis in patients with diabetes. In both cases, immediate fasciotomy was performed and appropriate empiric antimicrobial therapy and intensive care were administered. However, the two patients died on Day 2 and Day 11, respectively, after admission as a result of multiple organ failure. When patients present with a rapid onset of skin necrosis and progressive sepsis, an Aeromonas sobria infection or Vibrio infection should be considered in the differential diagnosis.

A possible new cause of spa bath folliculitis: Aeromonas hydrophila

A 34-year-old man presented with a pubic eruption of 4 weeks duration, affecting both himself and his partner. He had been treated unsuccessfully with intravenous and oral dicloxacillin. The eruption was a severely inflammatory folliculitis, with haemo-serous exudate and marked oedema. A clinical diagnosis of herpes simplex virus folliculitis was disproved when routine bacteriology isolated Aeromonas hydrophila and multiple viral polymerase chain reaction studies were negative. Histology demonstrated a chronic folliculitis with no organisms present. Both he and his partner were treated with oral ciprofloxacin 500 mg bd for 6 weeks with clinical clearance of infection, but both developed a scarring alopecia. Infection was attributed to possible contamination of a poorly maintained home spa bath with A. hydrophila.

Necrotizing soft-tissue infections and sepsis caused by Vibrio vulnificus compared with those caused by Aeromonas species

BACKGROUND

Vibrio and Aeromonas species, which can cause necrotizing fasciitis and primary septicemia, are members of the Vibrionaceae family and thrive in aquatic environments. Because the clinical symptoms and signs of necrotizing fasciitis and sepsis caused by these two bacteria are similar, the purposes of this study were to describe the clinical characteristics of Vibrio vulnificus and Aeromonas infections, to analyze the risk factors for death, and to compare the effects of surgical treatment on the outcome.

METHODS

The cases of thirty-two patients with necrotizing soft-tissue infections and sepsis caused by Vibrio vulnificus (seventeen patients) and Aeromonas species (fifteen patients) were retrospectively reviewed over a four-year period. Surgical débridement or immediate limb amputation was initially performed in all patients. Demographic data, underlying diseases, laboratory results, and clinical outcome were analyzed for each patient in both groups.

RESULTS

Six patients in the Vibrio vulnificus group and four patients in the Aeromonas group died. The patients who died had significantly lower serum albumin levels than did the patients who survived (p < 0.05). The patients with a combination of hepatic dysfunction and diabetes mellitus had a higher mortality rate than those with either hepatic disease or diabetes mellitus alone (p < 0.05). The patients with Vibrio vulnificus infections had a significantly lower systolic blood pressure at presentation (p = 0.006). The patients with Aeromonas infections who died had significantly lower white blood-cell counts (p = 0.03) with significantly fewer numbers of segmented white blood cells than those who died in the Vibrio vulnificus group (p = 0.01).

CONCLUSIONS

The contact history of patients with a rapid onset of cellulitis can alert clinicians to a differential diagnosis of soft-tissue infection with Vibrio vulnificus (contact with seawater or raw seafood) or Aeromonas species (contact with fresh or brackish water, soil, or wood). Early fasciotomy and culture-directed antimicrobial therapy should be aggressively performed in those patients with hypotensive shock, leukopenia, severe hypoalbuminemia, and underlying chronic illness, especially a combination of hepatic dysfunction and diabetes mellitus.

Skin and Soft-Tissue Infections among Tsunami Survivors in Southern Thailand

Among 777 patients transferred to 4 hospitals in Bangkok from southern Thailand after the tsunami of 26 December 2004, there were 515 with skin and soft-tissue infections. The most common organisms isolated were Aeromonas species (145 [22.6%] of 641 isolates from 305 patients). Most isolates were susceptible to aminoglycosides, third- and fourth-generation cephalosporins, quinolones, and imipenem but were resistant to amoxicillin-clavulanate and first-generation cephalosporins.