Are mosque carpets' reservoirs for fungi causing superficial foot mycosis? A cross-sectional study in Riyadh, Saudi Arabia

The possibility of superficial foot mycoses to spread through contaminated mosque carpets between worshipers imposes a great health burden and is never addressed in Riyadh, SA. We aimed to assess the prevalence of fungal infections, especially human dermatophytosis acquired from mosque carpets, in five different regions of Riyadh, Saudi Arabia and establish a means of contamination control. A cross-sectional study of 100 mosques in Riyadh, Saudi Arabia, was conducted, using a multistage random cluster sampling technique. The study included mosques that had an ablution area and regularly hosted five prayers a day. Sterile swabs were used for sampling, and the samples were transported to the laboratory for culture and analysis using a micro-scan system. A total of 199 (65%) samples contained several fungal species. Rhodotorula (74%), Cladosporium (47%), Bipolaris (46.6%), other yeasts (43.7%), Alternaria (40%), dematiaceous molds (34%), Curvularia (32.4%), and Candida (31%) were the most frequently isolated species. Species belonging to several other genera were also detected. This study revealed a relatively high prevalence of fungal organisms in mosque carpets in Riyadh, suggesting the need for implementing new strategies and laws to increase the level of hygiene awareness among worshipers and mosque caretakers to limit the spread of foot fungal infections.

Characterization of Foot Mycetoma Using Sonography and Color Doppler Imaging

BACKGROUND AND OBJECTIVE

Mycetoma of the foot, commonly referred to as Madura foot, is a chronic granulomatous infection, which impacts vascularization of the affected region. This study aimed to evaluate foot mycetoma using Doppler and sonography techniques to identify the principle sonographic features and blood flow patterns associated with the condition.

MATERIALS AND METHODS

This was a cross-sectional prospective single-center study conducted at the Mycetoma Research Center (MCR) in Khartoum State, Sudan. Sixty patients with Madura foot were examined using a Duplex ultrasound machine with a 7-10 MHZ linear probe. Data was analyzed using SPSS software. The distribution of demographic data was evaluated by simple descriptive statistics. Statistical tests was performed using Student's independent t-tests to compare different forms of mycetoma and Chi-square tests to examine differences in blood flow patterns between fungal (eumycetoma) and bacterial (actinomycetoma) forms of the infection.

RESULTS

The presence of multiple cavities and aggregated grains were more common in eumycetoma than in actinomycetoma. The echotexture was significantly more heterogeneous in eumycetoma than in actinomycetoma (p = 0.03). Eumycetoma had higher vascularity than actinomycetoma.

CONCLUSION

Mycetoma has characteristic sonographic features and patterns of vascularity, which are essential to differentiate between the fungal and bacterial forms of mycetoma.

Persistent rash on feet

A 49-year-old Hispanic woman presented with a 4-month history of scaling and a macerated rash localized between her toes. The rash was malodorous, mildly erythematous, and sometimes associated with pruritus. The patient had no relevant medical history. Potassium hydroxide testing was performed and found to be negative. So a Wood's lamp was used to examine the patient's toes--and it revealed the diagnosis. WHAT IS YOUR DIAGNOSIS? HOW WOULD YOU TREAT THIS PATIENT?

Prospective case-control study of toe tip necrosis syndrome (TTNS) in western Canadian feedlot cattle

A case-control study was conducted to investigate potential risk factors for toe tip necrosis syndrome (TTNS) in western Canadian feedlot cattle. Feedlot veterinarians provided hooves from 222 animals that died of either TTNS ("cases") or from all other causes ("controls"). The claws were sectioned by researchers to confirm the diagnoses; there was very good agreement between the practitioners' field diagnosis and that of the researchers (Cohen's kappa = 0.81; P < 0.001). The sole thickness of the apical white line region was thinner (P < 0.001) in the cases (3.74 mm) than the controls (4.72 mm). Claws from cases were 5.0 [95% confidence interval (CI): 1.5 to 8.6; P < 0.001] and 7.3 times (95% CI: 1.5 to 69.3; P < 0.01) more likely than those of controls to yield a heavy growth of Escherichia coli and Trueperella pyogenes, respectively. Cases were 4.4 times (95% CI: 4.4 to 22.9; P < 0.001) more likely to be acutely/transiently infected with bovine viral diarrhea virus than were controls. The findings support the hypothesis that TTNS is initiated by excessive wear along the white line, leading to separation and bacterial colonization of the 3rd phalangeal bone (P3) and associated soft tissues.

Foot Infections

Infections of the foot are very variable, some being complex in nature, causing pain, morbidity, and even mortality. In patients with diabetes mellitus, foot infections are common, ranging from chronic bacterial or fungal infections to serious limb-threatening ones. To manage infections, a sound knowledge of anatomy is essential. This article reviews the problems with respect to recent evidence and provides pathways to management and suggestions of changes with potential to wound healing.

Infectious lameness among migratory sheep and goats in north-west India, with particular focus on anaerobes

Various bacterial species, particularly Dichelobacter nodosus, Fusobacterium necrophorum, Trueperella pyogenes (previously Arcanobacterium pyogenes) and Treponema spp., have been implicated in infectious conditions manifesting in lameness in sheep and goat populations. The current study reports the causes of infectious lameness in the north-western Himalayan region, particularly Himachal Pradesh (HP), where no such study has been conducted in the past. Among a total surveyed population of 27,586 animals, comprised of 15,006 sheep and 12,580 goats, 216 samples were collected from foot lesions. A total of 6.48% (14/216) samples were positive for D. nodosus, 20.83% (45/216) for F. necrophorum and 20.37% (44/216) for T pyogenes. In three instances, all of the three aforementioned bacteria were present in a single foot lesion. Most of the positive samples were from areas in the state of HP adjoining the state of Jammu and Kashmir (J&K), where footrot is endemic. The confirmation of footrot in HP and the fact that F. necrophorum and T pyogenes were detected from cases of foot/hoof infection in high numbers emphasises thatthese organisms play an important role in inducing morbidity in migratory sheep and goats. The present investigation also confirms the detection of D. nodosus from cases of footrot for the first time from HP. With new reports identifying F. necrophorum as a pathogen with a potential role in aggravating infection caused by footrot, the development of a combined vaccine to prevent lameness in sheep and goats in the north-western Himalayan region has been suggested.

Mouth in Foot Disease

Toothpicks are commonly used household items that rarely cause serious injury or infection. Toothpick-related injuries often occur due to ingestion with subsequent trauma/infection at distal sites within the gastrointestinal tract; however, cardiovascular, pleural, and soft tissue infections have been reported. Eikenella corrodens is a gram-negative, facultative anaerobic bacillus found in oral flora associated with bite wound infections. A few case reports describe E. corrodens osteomyelitis from toothpick puncture wounds. We report a case of foot cellulitis and abscess in an elderly diabetic after toothpick puncture injury that was unresponsive to empiric antibiotics. Wound cultures grew E. corrodens and rare Peptostreptococcus species. E. corrodens is resistant to first-generation cephalosporins, macrolides, aminoglycosides, clindamycin, and metronidazole. This case highlights the insidious nature of E. corrodens infections and the need to tailor empiric antibiotics for skin and soft tissue infections based on the mechanism of injury. In addition, this case stresses the importance of protective footwear in diabetics and serves as a cautionary tale regarding the use of seemingly innocuous toothpicks.

Mycetoma of the Foot Caused by Madurella Mycetomatis in Immigrants from Sudan

BACKGROUND

Mycetoma is a chronic and destructive infection caused by either fungus or bacteria. Mycetoma has a characteristic clinical presentation of a triad of tumor-like swelling, draining sinuses, and macroscopic grains. Mycetoma infection is extremely rare in Israel; however, in view of the recent immigration from mycetoma-hyperendemic regions of Africa to Israel, physicians in Israel may encounter this infection.

OBJECTIVES

To present two cases of mycetoma caused by Madurella mycatomatis in immigrants from endemic regions in Sudan treated at our hospital, and review the current literature.

CONCLUSIONS

Health care professionals in Israel should suspect mycetoma in patients from endemic countries who present with tumor-like swelling especially in the lower extremity. Health care workers should be able to recognize mycetoma and provide the optimal treatment before the lesion progresses to an advanced and disabling disease.

Case report: Actinomycetoma caused by Nocardia aobensis from Lao PDR with favourable outcome after short-term antibiotic treatment

BACKGROUND

Mycetoma is a neglected, chronic, localized, progressively destructive, granulomatous infection caused either by fungi (eumycetoma) or by aerobic actinomycetes (actinomycetoma). It is characterized by a triad of painless subcutaneous mass, multiple sinuses and discharge containing grains. Mycetoma commonly affects young men aged between 20 and 40 years with low socioeconomic status, particularly farmers and herdsmen.

METHODOLOGY/PRINCIPAL FINDINGS

A 30 year-old male farmer from an ethnic minority in Phin District, Savannakhet Province, Lao PDR (Laos) developed a painless swelling with multiple draining sinuses of his right foot over a period of approximately 3 years. X-ray of the right foot showed osteolysis of tarsals and metatarsals. Aerobic culture of sinus discharge yielded large numbers of Staphylococcus aureus and a slow growing Gram-positive rod. The organism was subsequently identified as Nocardia aobensis by 16S ribosomal RNA gene sequencing. The patient received antimicrobial treatment with amikacin and trimethoprim-sulfamethoxazole according to consensus treatment guidelines. Although slight improvement was noted the patient left the hospital after 14 days and did not take any more antibiotics. Over the following 22 weeks the swelling of his foot subsequently diminished together with healing of discharging sinuses.

CONCLUSION

This is the first published case of Actinomycetoma caused by Nocardia aobensis and the second case of Actinomycetoma from Laos. A treatment course of only 14 days with amikacin and trimethoprim-sulfamethoxazole was apparently sufficient to cure the infection, although long-term treatment up to one year is currently recommended. Treatment trials or prospective descriptions of outcome for actinomycetoma should investigate treatment efficacy for the different members of Actinomycetales, particularly Nocardia spp., with short-term and long-term treatment courses.

Staphylococcus spp., Streptococcus canis, and Arcanobacterium phocae of healthy Canadian farmed mink and mink with pododermatitis

Pododermatitis is a disease of concern for mink breeders in Canada and worldwide, as it causes discomfort and lowers the breeding rates on farms affected by the disease. Unfortunately, the etiology and pathogenesis of pododermatitis are still unknown. In this study, we compared Staphylococcus spp. and Streptococcus canis isolates from healthy mink with isolates from animals with pododermatitis on 2 farms in Ontario. Almost all hemolytic Staphylococcus spp. isolated were shown to be Staphylococcus delphini Group A by 16S ribosomal ribonucleic acid (rRNA) sequence analysis and polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) did not reveal any S. delphini or S. canis clonal lineages specifically associated with pododermatitis, which suggests that these bacteria do not act as primary pathogens, but does not dismiss their potential roles as opportunistic pathogens. While S. delphini and S. canis were the most prevalent bacterial pathogens in mink pododermatitis, they were also present in samples from healthy mink. Arcanobacterium phocae is occasionally isolated from pododermatitis cases, but is difficult to recover with conventional culture methods due to its slow growth. A quantitative real-time PCR was developed for the detection of A. phocae and was tested on 138 samples of footpad tissues from 14 farms. The bacterium was detected only in pododermatitis-endemic farms in Canada and was at higher concentrations in tissues from infected footpads than in healthy tissues. This finding suggests that A. phocae is involved in the pathogenesis of pododermatitis.

A forgotten disease in a returning traveler from Thailand

Cutaneous diphteria is a forgotten disease. We must consider this in our differential diagnosis, not only when a patient presents with a cutaneous ulcer and has travelled to tropical areas, but also in patients who subsist in low socio-economic conditions, especially in homeless people and people with a history of alcohol or drug abuse. Vigilance for this forgotten disease is warranted because most physicians in developed countries have never seen one case. In an era of increasing globalisation, we might see more cases in the future. We report a case of a foot infection with a non toxigenic C. diptheriae biovar gravis in a 16 year old girl, who has travelled to Thailand.

Comparative in vitro activity of ceftaroline, ceftaroline-avibactam, and other antimicrobial agents against aerobic and anaerobic bacteria cultured from infected diabetic foot wounds

Foot infections are the most common infectious complication of diabetes. Moderate to severe diabetic foot infections (DFI) are typically polymicrobial with both aerobic and anaerobic organisms. The role of MRSA in these wounds has become an increasing concern. To determine if the addition of avibactam, a novel non-beta-lactam beta-lactamase inhibitor, to ceftaroline would be more active than ceftaroline alone, we tested 316 aerobic pathogens and 154 anaerobic recovered from patients with moderate to severe DFI, and compared ceftaroline with and without avibactam to other agents. Testing on aerobes was done by broth microdilution and by agar dilution for anaerobes, according to CLSI M11-A8, and M7-A8 standards. Ceftaroline-avibactam MIC90 for all Staphylococcus spp. including MRSA was 0.5 μg/mL, and for enterococci was 1 μg/mL. The MIC90s for enteric Gram-negative rods was 0.125 μg/mL. The addition of avibactam to ceftaroline reduced the ceftaroline MICs for 2 strains of resistant Enterobacter spp. and for 1 strain of Morganella. Against anaerobic Gram-positive cocci ceftaroline-avibactam had an MIC90 0.125 μg/mL and for clostridia 1 μg/mL. Avibactam improved ceftaroline's MIC90s for Bacteroides fragilis from >32 to 2 μg/mL and for Prevotella spp. from >32 to 1 μg/mL. Ceftaroline alone demonstrates excellent in vitro activity against most of the aerobes found in moderate to severe DFI. The addition of avibactam provides an increased spectrum of activity including the beta-lactamase producing Prevotella, Bacteroides fragilis and ceftaroline resistant gram-negative enteric organisms.

Tubercular dactylitis with discharging sinus in an adult patient

Tubercular dactylitis, a term used for tuberculosis of short and tubular bones of hands and feet, rarely shows involvement of the foot. It is more commonly found in children as compared with adults. A 27-year-old male, came with history of discharging sinus over dorsum of great toe of right foot. Clinical assessment led to the suspicion of tuberculosis which was later confirmed by biopsy. This case highlights the importance relying on clinical impression and considering tuberculosis as an aetiology even at unusual sites of involvement.

Feed enzyme supplementation does not ameliorate Foot Pad Dermatitis in broiler chickens fed on a corn-soyabean diet

1. Foot Pad Dermatitis (FPD) can be a serious health, quality and welfare problem in poultry production, with a significant affect on the economics of production. The physico-chemical properties of (NSP) have been correlated with increases in excreta viscosity and adherence, and hence FPD in broiler chickens. 2. Two broiler experiments were conducted to evaluate the effects of different dietary non-starch polisaccharide (NSP) applications to corn-soyabean based diets in replicated floor pens. In addition to live performance, the incidence and severity of FPD was scored and, in experiment 2, intestinal viscosity and ammonia volatilization were measured. 3. Live performance did not vary with the different treatments in either experiment and the incidence and severity of FPD, and ammionia volatisation in experiment 2, were unaffected. However, birds reared on enzyme supplemented diets had lower (P < 0·001) intestinal viscosity levels in experiment 1. 4. In this study with corn-soyabean meal based diets, dietary enzyme supplementation had no affect on the incidence and severity of FPD. The lack of an association between the excreta viscosity and FPD is attributed to the multifactorial etiology of this condition.

[Diabetic foot infections: microbiological aspects]

The diagnosis of wound infection is based on clinical signs and local and/or systemic inflammation. Therefore, the examination has a major role in the diagnosis of infected lesions of the foot. Once the clinical diagnosis of infection is made, the next step is to determine the etiology with the aim to undertake a rational and appropriate treatment. The most reliable method for assessing microbiological etiology is the specimen of material from infected lesion to perform a bacterioscopic examination and culture. The microorganisms involved in the etiology of diabetic foot depends on the type of injury and on specific patient features (antibiotic therapy, previous hospitalization). The most frequently detected pathogen is Staphylococcus aureus. Mild infections are mostly caused by Gram positive cocci, with a prevalence of S. aureus. Moderate infections are mostly supported by pyogenic Gram positive cocci, but also Gram-negative bacteria can be involved. In severe infections the etiology is polymicrobial. As regards the involvement of fungi in diabetic foot infections data are few and mostly conflicting.

Methicillin-resistant Staphyloccocus aureus heel abscess: an uncommon emergency department diagnosis

Heel abscesses present as heel pain that progressively worsens, with associated tenderness and fullness at the heel pad. Radiological studies like computed tomography, magnetic resonance imaging, or ultrasound can help correctly diagnose a heel pad abscess. Generally, these patients require i.v. antibiotics and operative management to adequately drain the abscess. It is recommended to avoid incising the plantar aspect of the heel to minimize chronic post-drainage heel pain.

[Chronic fistula of the forefoot in a Moroccan man: bone chromomycosis due to Phialophora verrucosa]

Chromomycosis is a chronic infection caused by various fungi. Bone involvement is exceptional. The purpose of this report is to describe a case of chromoblastomycosis localized on the tarsal bone in a 27-year-old man from southern Morocco. The patient was a former barefoot long-distance runner. He presented with thickening of the skin with a cutaneous fistula on the left forefoot. These manifestations had been ongoing for 2 years. Imaging demonstrated scattered lytic lesions involving tarsal bone and the base of the third metatarsus. Definitive diagnosis was based on direct mycological examination and anatomopathology. Medical and surgical treatment led to stabilization of the lesions. No recurrence was observed during follow-up examination two years later.

MRSA and diabetic foot wounds: contaminating or infecting organisms?

Although infection is a well-recognized barrier to healing, evidence has emerged that wound colonization with methicillin-resistant Staphylococcus aureus (MRSA) has the same effect, which has been quantified as increasing the time to healing twofold. MRSA is a concern for those with diabetic foot ulcers based on evidence of impaired healing when it is present in the wound. However, many studies have found the bacterial content of diabetic foot ulcers to be polymicrobial, which necessitates MRSA being placed in this environmental context. Multiple variables contribute to the development of infection, including the host response, tissue perfusion, ulcer depth, ulcer location, and an adequate source of nutrition. In view of these factors, it is difficult to attribute infection to one bacterial species.

The role of radiology in nerve function impairment and its musculoskeletal complications in leprosy

Conventional techniques, such as plain radiography and bone-scintigraphy, were used in the past to evaluate skeletal changes in patients with leprosy. More recent publications focus on radiological imaging of affected nerves, and involve advanced modalities such as Computed Tomography (CT-scan), Ultrasonography (US), and Magnetic Resonance Imaging (MRI). US and MRI can play an especially important role in the evaluation of nerve involvement in newly diagnosed patients, and also during leprosy reactions. This is important, because when nerve involvement is diagnosed in time, it may be reversible with adequate treatment. Radiological modalities can also play an important role during the followup of patients with leprosy with nerve function impairment. Skeletal and soft-tissue abnormalities occur, even after treatment. The so-called neuropathic foot is a well known consequence. Because of nerve function impairment, there is a constant risk of developing ulcers and subsequent osteomyelitis, or neuro-osteoarthropathy (Charcot foot or tarsal disintegration), which can lead to the amputation of the affected limb. Different radiological modalities can be used during the evaluation and follow-up of patients with leprosy with a neuropathic foot. With this up-to-date review, we highlight the importance and potential role of radiological imaging techniques in leprosy.

Identification of Porphyromonas levii isolated from clinical cases of bovine interdigital necrobacillosis by 16S rRNA sequencing

Laboratories use pigmentation, antibiotic susceptibility, and biochemical tests to identify anaerobic organisms that play a role in bovine interdigital necrobacillosis (bovine foot rot). In this study, 16S rRNA gene sequencing was used to identify strains to the species level that were originally classified as Prevotella or Porphyromonas spp by conventional phenotype assessment methods. Of 264 qualified strains from ceftiofur clinical trials, 241 isolates were definitively identified by 16S rRNA sequencing as Porphyromonas levii. Similarly, of 275 qualified strains from tulathromycin clinical trials, 156 isolates were definitively identified by 16S rRNA sequencing as P. levii. The predominance of P. levii in this study supports the role of this organism as an associative agent of bovine foot rot and may have implications for routine laboratory diagnosis.

In vitro susceptibility of bovine digital dermatitis associated spirochaetes to antimicrobial agents

Bovine digital dermatitis (BDD) is an infectious lameness in cattle, which has a large global impact in terms of animal welfare and cost. The majority of evidence suggests that spirochaetes are the aetiological agent of this disease. The aim of this study was to identify the susceptibility of BDD associated spirochaetes to a range of antimicrobial agents with a view to potential usage in vivo to treat this widespread cattle disease. A microdilution method was adapted to determine the in vitro susceptibilities of 19 UK digital dermatitis spirochaetes (6 Treponema medium/Treponema vincentii-like, 8 Treponema phagedenis-like and 5 Treponema denticola/Treponema putidum-like) to eight relevant antimicrobials. The BDD spirochaetes exhibited the highest susceptibility to penicillin and erythromycin and this information may now be used to aid development of efficacious treatments. This study has also identified that BDD spirochaete T167 is spectinomycin resistant and that the likely biological basis is a point mutation in the 16S rRNA gene. Interestingly, nearly all Brachyspira isolate 16S rRNA gene sequences in Genbank have this substitution, suggesting it may be responsible for the characteristic spectinomycin resistance reported for the Brachyspira genus.

A clinical and radiological follow-up study in leprosy patients with asymptomatic neuropathic feet

OBJECTIVES

An MRI study done in 2000 on 10 leprosy patients with neuropathic feet, without clinical complications such as ulcerations, osteomyelitis or Charcot deformities revealed abnormalities in nine patients, with degradation, interruption of subcutaneous fat and effusion/synovitis, all located in the first metatarsophalangeal (MTP) region. Since these MRI abnormalities may precede clinical complications of the foot, a follow-up study was performed.

DESIGN

A new evaluation was based on a clinical examination and an MRI of the same patients who participated in the initial study.

RESULTS

Four patients were lost to follow-up. Average follow-up period was 4-6 years. MRI abnormalities in the MTP 1 region in the first study were no longer visible in three patients, but were still present in two patients. In six patients new MRI findings were found, without clinical evidence of ulceration, osteomyelitis or Charcot deformity. No relationship was found between MRI findings in the MTP 1 region at the start of the study and the development of foot ulcers, callus or skin fissures in the MTP 1 region during follow-up.

CONCLUSION

MRI findings of interruption and infiltration of the subcutaneous fat in leprosy patients with uncomplicated neuropathic feet do not necessarily have any clinical implication for the development of future foot problems.

A cardiologist's experience undergoing quadruple coronary artery bypass surgery

This article describes the past medical history of a 76-year-old cardiologist, the symptoms which led him to have a stress echocardiogram, the results of his coronary angiography, his experience undergoing quadruple coronary artery bypass surgery, his recovery at home, his readmission and hospitalization for a massive left pleural effusion and an infection of his left foot, and his recovery at home.

Fluorescence in situ hybridization analysis of hindgut bacteria associated with the development of equine laminitis

Carbohydrate-induced laminitis in horses is characterized by marked changes in the composition of the hindgut microbiota, from a predominantly Gram-negative population to one dominated by Gram-positive bacteria. The objective of this study was to monitor changes in the relative abundance of selected hindgut bacteria that have previously been implicated in the pathophysiology of equine laminitis using fluorescence in situ hybridization (FISH). Caecal cannulae were surgically implanted in five Standardbred horses and laminitis induced by oral administration of a bolus dose of oligofructose. Caecal fluid and faecal specimens were collected over a 48 h period at 2 to 4 h intervals post-oligofructose administration and subjected to FISH using probes specific for nine bacterial groups to determine changes in their relative abundance compared with total bacteria hybridizing to the generic EUBMIX probe. Additionally, hoof biopsies were taken over the course of the experiment at 6 h intervals and evaluated for histopathological changes consistent with laminitis, allowing changes in hindgut microbiota to be correlated with the onset of lesions in the foot. Of the microorganisms specifically targeted, streptococci of the Streptococcus bovis/equinus complex were the only bacteria that consistently proliferated in both caecal fluid and faeces immediately before the onset of histological signs of laminitis. Furthermore, lactobacilli, Enterobacteriaceae, Allisonella histaminiformans, enterococci, Bacteroides fragilis, Mitsuokella jalaludinii and Clostridium difficile did not establish significant populations in the hindgut before the onset of equine laminitis.

Linezolid tissue penetration and serum activity against strains of methicillin-resistant Staphylococcus aureus with reduced vancomycin susceptibility in diabetic patients with foot infections

OBJECTIVES

Linezolid soft tissue penetration and serum antimicrobial activity were analysed in six patients with peripheral vascular disease and severe diabetic foot infections requiring surgical intervention.

METHODS

Blood draws (1, 3, 6, 9 and 12 h after initiation of a 1 h infusion) and a viable soft tissue sample at the site of infection were obtained in patients receiving linezolid (600 mg every 12 h) on the day of surgery. Concentrations of linezolid were determined by HPLC in both tissue (pre-treated with tissue lysis buffer) and serum. In addition, serum inhibitory and bactericidal activity (dilution titres 1:2-1:32) of linezolid was determined in these patients against strains of methicillin-resistant Staphylococcus aureus (MRSA) with reduced susceptibility to vancomycin (vancomycin MICs = 2, 4, 8, 256 and >256 mg/L).

RESULTS

Linezolid concentrations in tissue were found to be 51% (range, 18% to 78%) of simultaneous serum concentrations. Rapid (1 h) and prolonged (12 h) inhibitory activity (titres > or = 1:2) was observed for linezolid against each of the study isolates. Furthermore, bactericidal activity (titres > or = 1:2) was observed for at least 6 h (50% of the dosing interval) against four of these five strains.

CONCLUSIONS

These findings suggest that linezolid could be effective in the treatment of multidrug-resistant MRSA even when concentrations at the infection site are diminished due to impaired blood flow.

An infectious disease update on antibiotics: emerging resistance

Podiatric physicians often encounter infectious processes in the lower extremity in inpatient and outpatient settings. Bacterial resistance to antibiotics is a growing concern for clinicians treating these infections, especially in complex patients who have immune compromise such as diabetes. Although a number of antibiotic options are available for the treatment of lower-extremity soft tissue and bone infections, a careful examination of bacterial susceptibilities, drug resistance, and treatment efficacy can result in better patient care and limb salvage.

High prevalence of ischaemia, infection and serious comorbidity in patients with diabetic foot disease in Europe. Baseline results from the Eurodiale study

AIMS/HYPOTHESIS

Large clinical studies describing the typical clinical presentation of diabetic foot ulcers are limited and most studies were performed in single centres with the possibility of selection of specific subgroups. The aim of this study was to investigate the characteristics of diabetic patients with a foot ulcer in 14 European hospitals in ten countries.

METHODS

The study population included 1,229 consecutive patients presenting with a new foot ulcer between 1 September 2003 and 1 October 2004. Standardised data on patient characteristics, as well as foot and ulcer characteristics, were obtained. Foot disease was categorised into four stages according to the presence or absence of peripheral arterial disease (PAD) and infection: A: PAD -, infection -; B: PAD -, infection +; C: PAD +, infection -; D: PAD +, infection +.

RESULTS

PAD was diagnosed in 49% of the subjects, infection in 58%. The majority of ulcers (52%) were located on the non-plantar surface of the foot. With regard to severity, 24% had stage A, 27% had stage B, 18% had stage C and 31% had stage D foot disease. Patients in the latter group had a distinct profile: they were older, had more non-plantar ulcers, greater tissue loss and more serious comorbidity.

CONCLUSIONS/INTERPRETATION

According to our results in this European cohort, the severity of diabetic foot ulcers at presentation is greater than previously reported, as one-third had both PAD and infection. Non-plantar foot ulcers were more common than plantar ulcers, especially in patients with severe disease, and serious comorbidity increased significantly with increasing severity of foot disease. Further research is needed to obtain insight into the clinical outcome of these patients.

Mycetoma in children: experience with 15 cases

BACKGROUND

Mycetoma is a chronic infection caused by aerobic actinomycetes and filamentous fungi. It is an occupational disease frequent in tropical countries and is uncommon in children.

METHODS

A retrospective (25 years) report of mycetomas was conducted in children less than 15 years of age. Each of the cases was studied clinically and proven with microbiologic tests: direct examinations (to identify and classify the grains), cultures and identification based on morphology and biochemical tests. The therapeutic experience of the cases was also reviewed.

RESULTS

In a 25-year period, a total of 334 mycetomas were seen at our institution, 15 of which (4.5%) were in patients 15 years of age and younger (mean age: 11.2 years, age range: 6-15 years). Twelve cases were males and 3 females. The main clinical location was the foot in 10 of 15 (66.6%). Etiologies included 13 actinomycetomas and 2 eumycetomas. Etiologic agents were Nocardia brasiliensis in 12 cases, Nocardia asteroides in one and Madurella mycetomatis in 2. Eleven of the13 cases of actinomycetomas treated with trimethoprim-sulfamethoxazole plus diaminodiphenylsulfone were cured. The 2 failures were successfully treated with amoxicillin/clavulanate. One of the eumycetomas was cured with itraconazole therapy, whereas the other failed various treatments eventuating in surgical amputation.

CONCLUSIONS

Mycetomas are exceptional in children; in our setting, actinomycetomas are more frequent than eumycetomas. The clinical and microbiologic diagnosis is simple. Overall, treatment response is better for actinomycetomas than for eumycetomas.

[Gangrene with pyocyanic infection and osteitis in a patient presenting endemic Kaposi's sarcoma: case report from Benin]

Infectious complications involving chronic skin ulcers have been well document but superinfection of ulcerated Kaposi's sarcoma nodules by multiresistant germs has rarely been reported. The purpose of this report is to describe a case in a 57-year-old HIV-negative black African man. Kaposi's sarcoma nodules appeared suddenly and spread rapidly on the right leg with pain and fever. Onset was associated with a laboratory-documented inflammatory syndrome and two metatarsal bone defects. Amputation of the leg was required due to the presence of multiresistant germs: Pseudomonas aeruginosa, multiresistant Staphylococus aureus and Candida albicans. Occurrence of bone lesions beneath superinfected Kaposi's sarcoma nodules poses a challenge for differential diagnosis of the underlying cause, i.e. either Kaposi's sarcoma or infectious osteitis. Since etiologic diagnosis of bone defects requires facilities that are rarely available in an African hospital, surgical treatment is the only alternative if antimicrobial therapy fails.

Tuberculous pseudoaneurysm of the femoral artery complicated by cutaneous tuberculosis of the foot: a case report

An infected pseudoaneurysm of the right common femoral artery in a 69-year-old patient receiving methotrexate therapy was confirmed to have been caused by Mycobacterium tuberculosis. After surgical excision of the aneurysm and revascularization using femoral vein, cutaneous manifestations of M tuberculosis infection in the foot complicated the course. We hypothesized that methotrexate may have triggered the reactivation of dormant tuberculosis in this patient. Because extrapulmonary tuberculous pseudoaneurysms are clinically similar to other types of infected pseudoaneurysm, M tuberculosis infection should always be suspected during the initial diagnosis. We propose that mycobacterial cultures should be routine when initial cultures and Gram stain are negative.

Spontaneous bilateral ankle and midfoot sepsis in a nonimmunocompromised patient

We describe a 70-year-old nonimmunocompromised woman with spontaneous bilateral ankle and midfoot sepsis and a deep-space abscess of the right lower leg. Salvage of both limbs was achieved by aggressive bilateral soft-tissue and osseous debridement, including a four-compartment fasciotomy of the right lower leg, antibiotic-loaded polymethyl methacrylate bone cement implantation, delayed allogeneic bone grafting of the osseous defects impregnated with autologous platelet-rich plasma bilaterally, and external fixation immobilization, implantable bone growth stimulation, and split-thickness skin graft coverage of the right lower leg, ankle, and foot. Osseous incorporation of the bone grafts bilaterally occurred 8 weeks after surgery. No soft-tissue or osseous complications occurred during the postoperative period or at 18-month follow-up except for arthrofibrosis in the right ankle; there was no evidence of recurrent abscesses, sequestrum, or wound-related problems. A review of the literature regarding bilateral pedal sepsis and the techniques used for limb salvage in this patient are presented in detail.

In vitro degradation of equine keratin by dermatophytes and other keratinophilic fungi

Keratinolytic properties of two dermatophytes (Microsporum gypseum, Trichophyton mentagrophytes) and three moulds (Scopulariopsis brevicaulis, Alternaria alternata, Geotrichum candidum) isolated from diseased equine hooves were examined to improve the understanding of pathogenic mechanisms leading to equine onychomycosis. Equine hoof horn material and skin, as well as hoof keratin and dermal keratin extracted from corresponding tissues, were used as sole carbon and nitrogen sources in five test tubes for each fungus. Within 18 days, supernatants of all tubes were repeatedly examined for keratinolytic activity by SDS-PAGE and Western blot analysis. In addition, fungal growth rates were determined to identify the preferred tissue of the individual fungi. Among the fungi examined, M. gypseum was the most keratinolytic species, followed by T. mentagrophytes and S. brevicaulis. In the concentration applied, the moulds A. alternata and G. candidum showed minimal keratinolytic activity. With respect to growth rates, M. gypseum favoured hoof horn material, S. brevicaulis and G. candidum preferred skin as a keratin source, whereas for the other two fungi no clear preference was detectable.

Changes in equine hindgut bacterial populations during oligofructose-induced laminitis

In the horse, carbohydrate overload is thought to play an integral role in the onset of laminitis by drastically altering the profile of bacterial populations in the hindgut. The objectives of this study were to develop and validate microbial ecology methods to monitor changes in bacterial populations throughout the course of experimentally induced laminitis and to identify the predominant oligofructose-utilizing organisms. Laminitis was induced in five horses by administration of oligofructose. Faecal specimens were collected at 8 h intervals from 72 h before to 72 h after the administration of oligofructose. Hindgut microbiota able to utilize oligofructose were enumerated throughout the course of the experiment using habitat-simulating medium. Isolates were collected and representatives identified by 16S rRNA gene sequencing. The majority of these isolates collected belonged to the genus Streptococcus, 91% of which were identified as being most closely related to Streptococcus infantarius ssp. coli. Furthermore, S. infantarius ssp. coli was the predominant oligofructose-utilizing organism isolated before the onset of lameness. Fluorescence in situ hybridization probes developed to specifically target the isolated Streptococcus spp. demonstrated marked population increases between 8 and 16 h post oligofructose administration. This was followed by a rapid population decline which corresponded with a sharp decline in faecal pH and subsequently lameness at 24-32 h post oligofructose administration. This research suggests that streptococci within the Streptococcus bovis/equinus complex may be involved in the series of events which precede the onset of laminitis in the horse.

Improved diagnosis of virulent ovine footrot using the intA gene

Footrot is a mixed bacterial infection of the hooves of sheep. The gram-negative anaerobic bacterium Dichelobacter nodosus is the principal causative agent, with different strains causing diseases of different severity, ranging from benign to virulent. In Australia, in the state of New South Wales (NSW), only virulent footrot is subject to regulatory action, including quarantine. However, it is often difficult to distinguish benign footrot from virulent footrot in the initial stages of infection, or under adverse climatic conditions. The gelatin gel test, which measures the thermostability of secreted bacterial proteases, is the laboratory test most widely used in Australia to aid in the differential diagnosis of footrot. The proteases of virulent strains are, in general, more thermostable than the proteases of benign strains. However, there are some false positives in the gelatin gel test, which may lead to unnecessary quarantine procedures. We used Southern blot analysis on 595 isolates of D. nodosus from 124 farms on which sheep had benign or virulent footrot to test for the presence of the intA gene. We found that for D. nodosus strains which are stable in the gelatin gel test, there is a high correlation between the presence of the intA gene and the ability of the strain to cause virulent footrot. We also developed a PCR-based assay for the rapid detection of intA, which can be used to test DNA extracted from colonies grown on plates, or DNA extracted from cotton swabs of culture plates.

Proliferative pododermatitis (canker) with intralesional spirochetes in three horses

Spirochetes were identified histologically in canker (proliferative pododermatitis) in 3 horses. The data suggest that spirochetes may contribute to the pathology of equine chronic foot diseases similar to the manner in which they contribute to the pathology of bovine papillomatous digital dermatitis and contagious ovine digital dermatitis.