Severe Streptococcus zooepidemicus infection in a gardener

Artritis séptica por Streptococcus equi: reporte de un caso y revisión de la literatura

En humanos las infecciones producidas por Streptococcus equi son de rara ocurrencia, tienen una amplia variedad de formas de presentación, incluyendo com­promiso articular, el cual ha sido pocas veces descrito en humanos y aún menos en pacientes inmunocompetentes. En este artículo se presenta un caso de artritis séptica por S. equi que ocurrió por una exposición ocupacional en un paciente inmunocompetente y la revisión de la literatura relacionada.

Illustration of the difficulty of identifying Streptococcus equi strains at the subspecies level through a case of endocarditis in an immunocompetent man

We report a case of endocarditis caused by Streptococcus equi in an immunocompetent patient who was subsequently cured after appropriate antibiotherapy and cardiac surgery. However, it was challenging to identify the strain to the subspecies level, which highlights the necessity of developing reliable molecular tools to discriminate between the subspecies.

Aortic graft infection and mycotic aneurysm with Streptococcus equi zooepidemicus: two cases with favorable outcome of antibiotic treatment

Infections with Streptococcus equi zooepidemicus are rare and are associated with contact with animals or animal products. There are very few reports about infected vascular grafts or aneurysms with this etiology. We present two patients. The first is a 77-year-old man with an infected bifurcated graft four years after an open operation for an abdominal aortic aneurysm (AAA). The second is a 72-year-old man with a symptomatic mycotic AAA, treated with endovascular aneurysm repair. Both received prolonged treatment with bactericidal antibiotics and responded well. Follow-up time at present is 5.5 years for the first, and 4.5 years for the second, patient.

Spondylodiskitis secondary to Streptococcus equi subspecies zooepidemicus

Streptococcus equi subspecies zooepidemicus, traditionally classified under Group C Streptococci, is primarily a veterinary pathogen. Rarely, it may cause infections such as bacteremia, meningitis, endocarditis and pneumonia in humans. Musculoskeletal infections secondary to this pathogen are very uncommon. The authors present the first case of osteomyelitis due to S. zooepidemicus in a farmer who had close contact with a dead horse. The authors review all cases of osteoarticular infections secondary to this microbe, in addition to providing an overview of clinical manifestations, treatment and outcome of this infection.

Streptococcus equi subspecies zooepidemicus meningitis--a case report and review of the literature

A case is described of a 79-year-old man, trampled by his horses, who subsequently developed a wound infection and, later, meningitis. Streptococcus equi subsp. zooepidemicus was isolated as the causative organism. S. equi subsp. zooepidemicus, which carries the Lancefield Group C antigen, is an uncommon human pathogen but is commonly isolated from bacterial infections in animals, particularly horses. It is most commonly acquired by humans following animal contact. A review of the literature identified 20 previously described cases of S. equi subsp. zooepidemicus meningitis. Crude mortality following infection was 24%. All of the patients who died were over 70 years of age and the ingestion of unpasteurised dairy products was associated with all but one of the fatal cases. Hearing loss was a frequent complication, occurring in 19% of cases. Only 38% of patients made a complete recovery. Treatment regimes commonly included benzylpenicillin or a third-generation cephalosporin, with a mean treatment duration in survivors of 23 days.

Human bacterial arthritis caused by Streptococcus zooepidemicus: report of a case

Septic arthritis caused by Streptococcus zooepidemicus is a rare event in humans. Of the four cases reported in the literature, only two patients had direct animal contact, and the portal of entry remained unclear in all cases. We report herein the case of a patient who suffered a purulent arthritis of the left shoulder caused by S. zooepidemicus, successfully treated in our department. A diagnostic FDG-PET-CT scan ruled out other foci of infection, but detected a hyperkeratotic plantar chronic soft tissue lesion of the left foot, acquired in a paragliding accident 10 years earlier. The fact that the patient habitually took care of his horses barefoot in boots, identifies the cutaneous portal of entry as most likely. To our knowledge this is the first report of a septic arthritis caused by S. zooepidemicus where a cutaneous entry route is described.

Genome sequence of a Lancefield group C Streptococcus zooepidemicus strain causing epidemic nephritis: new information about an old disease

Outbreaks of disease attributable to human error or natural causes can provide unique opportunities to gain new information about host-pathogen interactions and new leads for pathogenesis research. Poststreptococcal glomerulonephritis (PSGN), a sequela of infection with pathogenic streptococci, is a common cause of preventable kidney disease worldwide. Although PSGN usually occurs after infection with group A streptococci, organisms of Lancefield group C and G also can be responsible. Despite decades of study, the molecular pathogenesis of PSGN is poorly understood. As a first step toward gaining new information about PSGN pathogenesis, we sequenced the genome of Streptococcus equi subsp. zooepidemicus strain MGCS10565, a group C organism that caused a very large and unusually severe epidemic of nephritis in Brazil. The genome is a circular chromosome of 2,024,171 bp. The genome shares extensive gene content, including many virulence factors, with genetically related group A streptococci, but unexpectedly lacks prophages. The genome contains many apparently foreign genes interspersed around the chromosome, consistent with the presence of a full array of genes required for natural competence. An inordinately large family of genes encodes secreted extracellular collagen-like proteins with multiple integrin-binding motifs. The absence of a gene related to speB rules out the long-held belief that streptococcal pyrogenic exotoxin B or antibodies reacting with it singularly cause PSGN. Many proteins previously implicated in GAS PSGN, such as streptokinase, are either highly divergent in strain MGCS10565 or are not more closely related between these species than to orthologs present in other streptococci that do not commonly cause PSGN. Our analysis provides a comparative genomics framework for renewed appraisal of molecular events underlying APSGN pathogenesis.

An outbreak of Streptococcus equi subspecies zooepidemicus associated with consumption of fresh goat cheese

Background

Streptococcus equi subspecies zooepidemicus is a rare infection in humans associated with contact with horses or consumption of unpasteurized milk products. On October 23, 2003, the National Public Health Institute was alerted that within one week three persons had been admitted to Tampere University Central Hospital (TaYS) because of S. equi subsp. zooepidemicus septicaemia. All had consumed fresh goat cheese produced in a small-scale dairy located on a farm. We conducted an investigation to determine the source and the extent of the outbreak.

Methods

Cases were identified from the National Infectious Disease Register. Cases were persons with S. equi subsp. zooepidemicus isolated from a normally sterile site who had illness onset 15.9-31.10.2003. All cases were telephone interviewed by using a standard questionnaire and clinical information was extracted from patient charts. Environmental and food specimens included throat swabs from two persons working in the dairy, milk from goats and raw milk tank, cheeses made of unpasteurized milk, vaginal samples of goats, and borehole well water. The isolates were characterized by ribotyping and pulsed-field gel electrophoresis (PFGE).

Results

Seven persons met the case definition; six had septicaemia and one had purulent arthritis. Five were women; the median age was 70 years (range 54–93). None of the cases were immunocompromized and none died. Six cases were identified in TaYS, and one in another university hospital in southern Finland. All had eaten goat cheese produced on the implicated farm. S. equi subsp. zooepidemicus was isolated from throat swabs, fresh goat cheese, milk tank, and vaginal samples of one goat. All human and environmental strains were indistinguishable by ribotyping and PFGE.

Conclusion

The outbreak was caused by goat cheese produced from unpasteurized milk. Outbreaks caused by S. equi subsp. zooepidemicus may not be detected if streptococcal strains are only typed to the group level. S. equi subsp. zooepidemicus may be a re-emerging disease if unpasteurized milk is increasingly used for food production. Facilities using unpasteurized milk should be carefully monitored to prevent this type of outbreaks.