Proteus mirabilis Keratitis: Risk Factors, Clinical Features, Treatment Outcomes, and Microbiological Characteristics.

PURPOSE: To characterize the risk factors, clinical presentations, management choices, and outcomes of Proteus mirabilis keratitis. METHODS: In this retrospective study, 26 culture-proven cases of P. mirabilis infections were diagnosed and treated between 1998 and 2019 at the University of Pittsburgh Medical Center. Medical records were available for 14 keratitis cases and were reviewed for demographic information, ocular risk factors, and treatment outcomes. RESULTS: Sixteen eyes of 14 patients were included in the study. The average age was 47.8 ± 19.3 years, with a median follow-up time of 6 months. The most common ocular risk factors were poor ocular surface and contact lens use in 57.1% and 42.9% of cases, respectively. Eleven of the 14 patients (78.6%) had positive corneal cultures, and 13 of the 14 patients (92.9%) had positive conjunctiva or eyelid cultures. All isolates were susceptible to ciprofloxacin, ofloxacin, moxifloxacin, gatifloxacin, and cefazolin. Surgical intervention was required in 4 patients (28.6%). Average LogMAR visual acuity was 1.3 ± 1.0 at presentation and 0.9 6 ± 1.0 at the most recent follow-up visit. CONCLUSIONS: Proteus mirabilis is an uncommon cause of microbial keratitis. Patients with poor ocular surface and those who use contact lens are at increased risk for developing this cause of keratitis. Empiric treatment with fortified antibiotics or fluoroquinolones seemed to provide effective coverage for P. mirabilis.

Safety analysis of a Russian phage cocktail: from metagenomic analysis to oral application in healthy human subjects.

Phage therapy has a long tradition in Eastern Europe, where preparations are comprised of complex phage cocktails whose compositions have not been described. We investigated the composition of a phage cocktail from the Russian pharmaceutical company Microgen targeting Escherichia coli/Proteus infections. Electron microscopy identified six phage types, with numerically T7-like phages dominating over T4-like phages. A metagenomic approach using taxonomical classification, reference mapping and de novo assembly identified 18 distinct phage types, including 7 genera of Podoviridae, 2 established and 2 proposed genera of Myoviridae, and 2 genera of Siphoviridae. De novo assembly yielded 7 contigs greater than 30 kb, including a 147-kb Myovirus genome and a 42-kb genome of a potentially new phage. Bioinformatic analysis did not reveal undesired genes and a small human volunteer trial did not associate adverse effects with oral phage exposure.

Preventive and therapeutic administration of an indigenous Lactobacillus sp. strain against Proteus mirabilis ascending urinary tract infection in a mouse model.

Probiotics are increasingly being considered as non-pharmaceutical and safe potential alternatives for the treatment and prevention of a variety of pathologies including urinary tract infections. These are the most common infections in medical practice and are frequently treated with antibiotics, which have generated an intense selective pressure over bacterial populations. Proteus mirabilis is a common cause of urinary tract infections in catheterised patients and people with abnormalities of the urinary tract. In this work we isolated, identified and characterised an indigenous Lactobacillus murinus strain (LbO2) from the vaginal tract of a female mouse. In vitro characterisation of LbO2 included acid and bile salts tolerance, growth in urine, adherence to uroepithelial cells and in vitro antimicrobial activity. The selected strain showed interesting properties, suitable for its use as a probiotic. The ability of LbO2 to prevent and even treat ascending P. mirabilis urinary tract infection was assessed using an experimental model in the mouse. Kidney and bladder P. mirabilis counts were significantly lower in mice preventively treated with the probiotic than in non-treated mice. When LbO2 was used for therapeutic treatment, bladder counts of treated mice were significantly lower although no significant differences were detected in P. mirabilis kidney colonisation of treated and non-treated animals. These results are encouraging and prompt further research related to probiotic strains and the basis of their effects for their use in human and animal health.

Investigating the antimicrobial activity of natural honey and its effects on the pathogenic bacterial infections of surgical wounds and conjunctiva.

Antimicrobial activities of 10-100% (wt/vol) concentrations of new honey, stored honey, heated honey, ultraviolet-exposed honey, and heated stored honey were tested against common human pathogens, including Escherichia coli, Entrobacter cloacae, Pseudomonas aeruginosa, Shigella dysenteriae, Klebsiella sp., Haemophilus influenzae, Proteus sp., Staphylococcus aureus, Streptococcus hemolyticus group B, and Candida albicans. Antimicrobial activity of honey was tested in acidic, neutral, or alkaline media. These were compared with similar concentrations of glucose in nutrient broth. Surgical wounds were made on the dorsum of mice and infected with S. aureus or Klebsiella sp. The wounds were treated with local application of honey four times a day or appropriate antibiotics and compared with control values. Bacterial conjunctivitis due to E. coli, Proteus sp., S. aureus, Klebsiella sp., and P. aeruginosa was induced in rats. Conjunctival application of honey four times a day or appropriate antibiotics was used for treatment and compared with control values. Growth of all the isolates was completely inhibited by 30-100% honey concentrations. The most sensitive microbes were E. coli, P. aeruginosa, and H. influenzae. Glucose showed less antimicrobial activity than honey, and many microbes showed positive culture even in 100% glucose. Heating to 80 degrees C for 1 hour decreased antimicrobial activity of both new and stored honey. Storage of honey for 5 years decreased its antimicrobial activity, while ultraviolet light exposure increased its activity against some of the microorganisms. Antimicrobial activity of honey was stronger in acidic media than in neutral or alkaline media. Single doses of honey used to prepare the 60% concentration in nutrient broth were bacteriocidal for P. aeruginosa and bacteriostatic for S. aureus and Klebsiella sp. during certain periods. Local application of raw honey on infected wounds reduced redness, swelling, time for complete resolution of lesion, and time for eradication of bacterial infection due to S. aureus or Klebsiella sp. Its potency was comparable to that of local antibiotics. Honey application into infective conjunctivitis reduced redness, swelling, pus discharge, and time for eradication of bacterial infections due to all the isolates tested.

Necrotizing fasciitis: improved survival with early recognition by tissue biopsy and aggressive surgical treatment.

BACKGROUND: Necrotizing fasciitis is a soft tissue gangrenous infection that is optimally treated by early diagnosis, radical surgical debridement of all involved necrotic tissue, broad spectrum antibiotics, and aggressive nutritional support. The early clinical diagnosis of an area of necrotizing fasciitis is difficult and frequently unreliable. We are reporting a series of cases in which an early, accurate diagnosis of necrotizing fasciitis was established by a frozen section tissue biopsy obtained at the bedside. METHODS: Over a 15-year period, a consecutive series of 43 patients had a bedside biopsy under local anesthesia with immediate frozen section evaluation. All patients were seen in the hospital or emergency room for treatment of an inflammatory process. RESULTS: These 43 patients had bedside biopsy and frozen section evaluation of an inflammatory process. Twelve patients were found to have necrotizing fasciitis. These patients were treated with immediate surgical debridement of all gross necrotic tissue, broad spectrum antibiotics, and adequate nutritional support. All of them survived. No cases of infectious gangrene occurred in the group of patients whose biopsy did not reveal necrotizing fasciitis. CONCLUSION: Frozen section tissue biopsy is a useful adjunct in establishing an early, accurate diagnosis of infectious gangrene.

Nonclostridial gas gangrene.

Although nonclostridial gas gangrene is not an unusual occurrence, relatively few cases including the distal lower extremity have been reported. Due to the serious nature of some of these infections, it is important for physicians to familiarize themselves with these nonclostridial crepitant infections, which are often confused with clostridial myonecrosis. Etiology, evaluation, and treatment is described by the authors. Also, a case study is presented.

[Prospects of using controlled-action lactoglobulins in the treatment of acute intestinal infections and dysbacteriosis in infants]. / Perspektivy primeneniia laktoglobulinov napravlennogo deistviia dlia lecheniia ostrykh kishechnykh infektsii i disbakterioza u detei rannego vozrasta.

The author summarizes the results of the preclinical study and clinical trial of the new biological drug lactoglobulin having an +anti-coli-proteus action. Shows that the drug holds promise in the treatment of infants with acute intestinal infections and dysbacteriosis as well as in the enrichment of lactic mixtures used for artificial feeding of premature children and babies referred to the risk group.

[Experimental study of a new biological preparation for treating E. coli infection and Proteus dysbacteriosis in young infants]. / Eksperimental'noe izuchenie novogo biologicheskogo preparata dlia lecheniia koli-infektsii i proteinogo disbakterioza u detei rannego vozrasta.

The action of a new biological preparation intended for the treatment of E. coli infection and Proteus dysbacteriosis in children has been studied in experiments on mice and suckling rabbits. The protective activity of anti-E. coli and anti-Proteus lactoglobulin has been found to exceed that of normal lactoglobulin 6- to 13-fold. When subjected to the action of proteolytic enzymes of the gastrointestinal tract, the preparation retains its preventive properties on the level of the native preparation, which confirms the possibility of the oral administration of the preparation in clinical practice without protecting it from the proteolytic action of the enzymes of the gastrointestinal tract.

[Vaccine from soluble antigens for the specific therapy of Proteus infection]. / Vaktsina iz rastvorimykh abtigenov dlia spetsificheskoi terapii proteinoi infektsii.

A vaccine prepared from Proteus soluble antigens obtained by the disintegration of microbial cells with hydroxylamine is proposed. In animal experiments the vaccine has proved to be nontoxic when injected in large single doses or in smaller doses over a prolonged period and capable of protecting mice and rabbits from Proteus infection. No pronounced postvaccinal complications have been registered in humans immunized with the vaccine. The possibility of using the vaccine for immunizing donors with the aim of obtaining hyperimmune anti-Proteus plasma and for the active vaccinal therapy of patients with Proteus infection has been shown.