Matthew C. Hall

Evidence of Multiple Virulence Subtypes in Nosocomial and Community-Associated MRSA Genotypes in Companion Animals from the Upper Midwestern and Northeastern United States

Objective: Not much is known about the zoonotic transmission of methicillin-resistant Staphylococcus aureus (MRSA) in companion animals in the United States. We report the rate of prevalence of S. aureus and MRSA recovered from clinical samples of animals requiring treatment at veterinary clinics throughout the upper midwestern and northeastern United States. Design: We compared phenotypes, genotypes, and virulence profiles of the MRSA isolates identified in companion animals, such as cats, dogs, horses, and pigs, with typical human nosocomial and community-associated MRSA (CA-MRSA) genotypes to assess implied zoonotic transmission or zooanthroponosis. Five hundred thirty-three coagulase-positive staphylococci (CPS) isolates recovered between 2006 and 2008 from a variety of animal-source samples were screened for S. aureus by S. aureus-specific 16S rDNA primers and were screened for methicillin-resistance. All MRSA isolates were genotyped by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and spa typing. They were also screened for common staphylococcal enterotoxin and adhesion genes by multiplex and singleplex PCR. Results: Among the 533 CPS isolates recovered, 66 (12.4%) were determined to be S. aureus and 24 (4.5%) were MRSA. The percent of animals that were positive for S. aureus were as follows: 6.6% (32 of 487) dogs, 39.6% (19 of 48) cats, 83.3% (10 of 12) horses, and 100% of pigs, rabbits, hamsters and rats. Notably, 36.4% of all S. aureus identified were MRSA. Methicillin-resistant S. aureus was present in clinical samples from 12 of 487 dogs (2.5%), 6 of 48 cats (12.5%), 5 of 12 horses (42%), and 1 of 2 pigs (50%). The 24 MRSA isolates resolved into 4 PFGE clones: USA100 (50%), USA300 (16.7%), USA500 (20.8%) and USA800 (12.5%) and 6 sequence types (ST5, ST8, ST105, ST830, and ST986) or 2 clonal complexes, CC5 and CC8. Five major virulence profiles (clusters A to E) were observed in these MRSA isolates. Genotypic and virulence profiles of cats and dogs were more similar to each other than to those of horses. A Panton-Valentine leukocidin positive isolate with ST8:USA300 background was identified in a pig causing skin and soft infection. Conclusion: The presence of human MRSA clones in these animals suggests possible reverse zoonotic transmission. This study reports the first case of a USA300 genotype in a pig. Presence of multiple virulence profiles within a MRSA genotype in these animals suggests the potential of emergence of new MRSA clones by gaining or losing additional virulence genes.

Parent Preferences for Pediatric Influenza Vaccine Attributes

Influenza vaccine is available as an intramuscular injection or an intranasal spray for eligible children. This study was conducted to examine parents’ preferences for influenza vaccine attributes and the attributes’ relative importance regarding the vaccination of their children. A quantitative Web survey was administered to 500 parents of children aged 2 to 12 years. The survey included general preference questions and conjoint (trade-off) questions. Parents most frequently selected efficacy, risk of temporary side effects, and physician recommendation as important vaccine attributes from a provided list (92%, 75%, and 59%, respectively). For attributes selected as important, parents rated the importance of the attribute; the highest mean importance ratings were given to efficacy, presence of mercury-containing preservative, and physician recommendation.The highest relative importance ratings in the conjoint section were given to efficacy and presence of mercury-containing preservative. Parental education on influenza vaccine efficacy and safety may help to improve pediatric vaccination rates.

Flap infection associated with medicinal leeches in reconstructive surgery: two new drug-resistant organisms.

The use of medicinal leeches in reconstructive surgery has proven value for the salvage of flaps with venous congestion but is associated with a risk of leech-acquired infection. The most common leech-associated organism is Aeromonas hydrophila, which antibiotic prophylaxis is typically directed against. The authors describe two new multidrug-resistant organisms acquired from medicinal leech therapy that resulted in flap infection. The evaluation of suspected leech-borne infection and management protocol for this leech-acquired resistant multi-organism infection is presented.

A Crunching Colon: Rectal Bezoar Caused by Pumpkin Seed Consumption

Rectal seed bezoars are an uncommon cause of fecal impaction, particularly in the United States. Although the literature has reported several cases of phytobezoars composed of various types of seeds, bezoars formed of pumpkin seeds have rarely been reported. We report a case of a man, aged 62 years, with a rectal bezoar composed of pumpkin seeds with complications necessitating extensive treatment, including manual disimpaction and colonoscopy.

Risk Factors for Severe Infection, Hospitalization, and Prolonged Antimicrobial Therapy in Patients with Babesiosis

Babesiosis is an emerging tick-borne disease transmitted by the hard tick Ixodes scapularis, which also transmits Lyme disease. Better gradation of prognostic indicators are needed to determine which patients may develop serious complications requiring hospitalization, and to provide early guidance on appropriate therapy. In this study, we evaluated 128 patients with smear or real time polymerase chain reaction-confirmed Babesia microti infections over a period of 16 years. Patients with asplenia or immunocompromising conditions were more likely to have severe infection (P < 0.01), require hospitalization (P < 0.01), or receive prolonged courses of antimicrobials (P < 0.01). Nausea or vomiting (P < 0.01) and diarrhea (P < 0.01) along with hyperbilirubinemia (P < 0.01) were predictive of severe infection, hospitalization, and prolonged antimicrobial therapy. Patients with concurrent Lyme disease were less likely to require hospitalization and had similar severity of disease and length of antibiotic treatment compared with those without Lyme disease.

Evidence of delayed dissemination or re-infection with Blastomyces in two immunocompetent hosts.

Relapse or recurrence of blastomycosis in patients is rare. Re-infection of a patient with blastomycosis has not been previously reported. In this report, we describe relapse or reinfection with Blastomyces in 2 immunocompetent patients. This is the first study in which genetic typing was performed on paired Blastomyces isolates from the same patient obtained months apart.

Incidental findings of blastomycosis lung nodules in five asymptomatic patients

Asymptomatic blastomycosis infections are rarely identified or described in the literature, but are believed to comprise 50% of cases. In this report we describe five sporadic cases of blastomycosis in asymptomatic patients. All of these cases were initially identified as incidental findings of lung nodules on CXR or CT. To our knowledge, these are the first detailed descriptions of asymptomatic blastomycosis, occurring as sporadic disease, in the literature.

Clinical Presentation and Outcomes of Children With Human Granulocytic Anaplasmosis

Background Adults with the tick-borne disease human granulocytic anaplasmosis (HGA) have a spectrum of acute febrile illnesses that, if untreated, might be severe. Clinical presentation and outcomes of children with HGA have been poorly described. Methods A retrospective analysis was conducted to determine the frequency, presentation, and outcomes of pediatric patients with HGA between 1994 and 2015 in a region of Wisconsin in which HGA is highly endemic. Patients with related International Classification of Diseases Ninth and Tenth Revision (ICD-9 and ICD-10, respectively) codes or positive HGA laboratory test results were evaluated and classified as having had confirmed, probable, or suspected HGA on the basis of the Centers for Disease Control and Prevention (CDC) case definition. The Fishers exact and Wilcoxon rank-sum tests were used in statistical comparisons. Results Of 187 children identified with possible HGA, 17 (9%) had confirmed, 75 (40%) had probable, and 91 (49%) had suspected infections. The number of cases rose sharply in 2010 and has remained between 16 and 36 cases per year since that time. A minority of children with confirmed or probable infections had elevated liver transaminase levels (33%), leukopenia (24%), thrombocytopenia (17%), or anemia (8%); 6 (7%) of these children required hospitalization. Children with evidence of concurrent HGA and Lyme disease (27% of confirmed or probable cases) had a higher risk of hospitalization (odds ratio, 6.55 [95% confidence interval, 1.11-38.78]). None of these children had life-threatening disease or died. Conclusions Evidence suggests that the frequency of HGA in children is increasing. Although most children had mild disease, doxycycline remains the treatment of choice, because outcome data for children without treatment remains limited.