Infective endocarditis in northeastern Thailand

Despite rigorous diagnostic testing, the cause of infective endocarditis was identified for just 60 (45.5%) of 132 patients admitted to hospitals in Khon Kaen, Thailand, during January 2010–July 2012. Most pathogens identified were Viridans streptococci and zoonotic bacteria species, as found in other resource-limited countries where underlying rheumatic heart disease is common.

[Endocarditis due to meticillin-resistant Staphylococcus aureus originating from pigs]

A 63-year-old woman with a kidney transplant was admitted with endocarditis caused by meticillin-resistant Staphylococcus aureus (MRSA). Once her antibiotic therapy had been adjusted to the sensitivity-pattern of the bacterial strain she recovered, without the need for surgical intervention. The isolated S. aureus was typed by multi-locus sequence typing as sequence type 398, a MRSA-strain that has recently been isolated from a high percentage of Dutch pigs. This is the first report of a life-threatening infection with this pig MRSA. This strain is genetically different from the globally dispersed nosocomial MRSA-strains, and also from the strains that have been epidemic for several years in the USA as the causative agent ofcommunity-acquired skin infections. The Dutch Working Group on Infection Prevention (WIP) has recently adjusted its guidelines to halt further spread of this strain, and advises that the population at risk (pig breeders, slaughterhouse personnel and veterinarians) be held in isolation when hospitalised until MRSA colonisation has been excluded. The patient described here, however, did not belong to this population at risk.

A case of polymicrobial endocarditis caused by anaerobic organisms in an injection drug user

Endocarditis is a serious complication of injection drug use most commonly caused by Staphylococcus aureus. We report a case of tricuspid valve polymicrobial bacterial endocarditis in an injection drug user from 3 oral anaerobes: Actinomyces odontolytica, Veillonella species, and Prevotella melaninogenica. The patient was believed to have acquired these organisms from his habit of licking the needle in order to gauge the strength of the cocaine prior to injection. The patient was successfully treated with a 6-week course of penicillin G and metronidazole. This case demonstrates the importance of a detailed history in designing empiric therapy.

[Q fever with endocarditis: clinical presentation and serologic follow-up of 21 patients]

AIM OF THE STUDY

The purpose of this study was to analyse the clinical and serological follow-up in 21 patients with Q fever endocarditis in Switzerland from 1981 to 1993.

PATIENTS AND METHODS

Criteria for Q fever endocarditis were the following: Coxiella burnetii phase I IgG > 1 : 2560 and IgA > 1 : 20 by indirect immunofluorescence. Methods to confirm the diagnosis include immunohistochemical demonstration of C. burnetii by microscopy in valvular material (1 case) and inoculation of this material in experimental animals (10 cases). Information on clinical course of the disease, laboratory abnormalities and treatment were obtained by chart review and a questionnaire sent to physicians who requested the serological tests for Q fever.

RESULTS

The average age of the patients was 47 years (15 men and 6 women). 64% of patients had a history of environmental exposure to C. burnetii. The median time of symptomatology before diagnosis was 5 months (1-108). 19/21 patients had valvular lesions, and 2/21 vascular Dacron prosthesis. Most patients presented with fever (18/21), congestive cardiac failure (14/21), weight loss (12/21), anemia (6/19), or thrombocytopenia (6/19). All the patients required antibiotic treatment. Cardiac surgery was performed in 15/21 patients. For 10 patients the geometric mean serological follow-up included at least titers at time of diagnosis (IgG anti-phase I antibodies 1 : 27024, IgA anti-phase I antibodies 1 : 685), at the end of therapy (IgG anti-phase I antibodies 1 : 2941, IgA anti-phase I antibodies 1 : 153) and 6 months after the end of therapy (IgG anti-phase I antibodies 1 : 368, IgA anti-phase I antibodies 1 : 40). The fall in anti-phase I titers was significant. During the clinical and serological outcome (median of 60 months and 69 months respectively) there was no recurrence of endocarditis and antibody titers to C. burnetii phase I remained low. Two patients died during the observation period, one from lung cancer, while the cause of death in the other was unknown.

CONCLUSIONS

Serology is the key to Q fever diagnosis. The duration of treatment, and the values to be used to establish cure of endocarditis, are not clearly defined. During the clinical and serological outcome (median of 60 months and 69 months respectively) there was no recurrence of endocarditis and antibody titers to C. burnetii phase I remained low.

Molecular analysis provides evidence for human to human transmission of Staphylococcus aureus endocarditis in non-drug abusers

Two cases of invasive Staphylococcus aureus are reported in which human to human transmission resulted in primary bacteremia and endocarditis. The identity of the organism was confirmed by phage typing, antibiograms, coagulase gene polymorphisms and ribotyping. This is the first documented case of such transmission not involving an intravenous drug abuser.

Does the bronchoscope propagate infection?

The flexible and rigid bronchoscopes traverse the nasopharynx or oropharynx and carry with them the indigenous microbial flora to distal regions and may thus inoculate the tracheobronchial tree and possibly the pulmonary parenchyma. The three potential consequences of this event include: (1) onset of new infection in the tracheobronchial tree or lung parenchyma or, if the patient has preexisting infection, further spread of infection locally or to extrapulmonary sites; (2) spread of infection from one patient to another via the bronchoscope, if the methods of disinfection and sterilization are inadequate; and (3) pseudoinfection due to cross-contamination of the bronchoscope, resulting in isolation of organisms from the bronchoscopic specimens of a patient who is clinically not infected. Review of the literature indicates that the last-mentioned consequence is more commonly encountered in clinical practice. The occurrence of pseudoinfection inevitably leads to costly and time-consuming procedures to guarantee that the patients are not infected. Rigorous adherence to sterilization and disinfection procedures and a common sense approach to protecting the uninfected patients and bronchoscopy personnel from infected patients and instruments will prevent the risk of propagating infection through the bronchoscope. This can be accomplished by establishing a set of policies regarding disinfection, sterilization, and protection of uninfected patients, as well as the bronchoscopist and paramedical personnel involved in bronchoscopy.

Zoonotic endocarditis

The so-called zoonotic endocarditis is transmitted from animals to humans and is frequently found in some cattle-raising countries. Brucella endocarditis is a destructive process of the aortic valve with abscess formation that commonly leads to heart failure. Q fever endocarditis is a more indolent infection, but it is also capable of producing severe valvular damage and hemodynamic compromise. Treatment of zoonotic endocarditis includes the prolonged administration of doxycycline in combination with other antimicrobial agents and a judicious use of valve replacement. Mortality of Brucella endocarditis has been decreased significantly by a medical-surgical approach to treatment. On the basis of serologic and valve tissue culture results, no treatment is consistently able to cure Q fever endocarditis, and thus mortality of this infection remains high.

Q-fever endocarditis in England and Wales, 1975-81

Endocarditis was recorded in 92 (11%) of 839 confirmed Q-fever infections reported for the Communicable Disease Report by laboratories between 1975 and 1981; Q-fever endocarditis accounted for approximately 3% of all cases of endocarditis reported. Two-thirds of the 92 reports were of men, and in both men and women endocarditis affected mainly young and middle-aged adults. Only one-third of Q-fever endocarditis patients were noted to have an underlying heart-valve lesion. There were also 30 reports of chronic Q-fever infection, and in 10 the primary clinical feature was liver disease. The laboratory data do not support the view that Q-fever endocarditis is a rare compilation of Coxiella burnetii infection, and the condition may be considerably underdiagnosed. Joint veterinary and medical investigations should be undertaken to establish the natural history of Coxiella burnetii infection in the U.K. in order to formulate policies for prevention of acute and chronic infection.

Community-acquired methicillin-resistant Staphylococcus aureus endocarditis in the Detroit Medical Center

Between June 1980 and September 1981 we evaluated 24 cases of endocarditis from methicillin-resistant Staphylococcus aureus. All of the cases occurred in drug addicts and all were community-acquired. The patients ranged in age from 21 to 59 years and represented an older population than that generally reported for bacterial endocarditis in addicts. Men and women were equally represented (one man presented twice). This unusually high proportion of women may reflect a difference in the rate and location of carriage of methicillin-resistant S. aureus compared with that of methicillin-sensitive staphylococci. Three patients died, one of whom had signed out of the hospital on the 14th day and returned moribund 27 days later. Vancomycin treatment for 28 days was adequate therapy for most patients.

Endocarditis from human-to-human transmission of Staphylococcus aureus

Endocarditis due to Staphlyococcus aureus developed in two drug abusers who used the same paraphernalia for parenteral injections. The phage type of the organism isolated from the blood and nasal secretions of the first patient was identical to that of the organism isolated from the blood of the second patient. The epidemiologic and microbiologic data from our cases indicate human-to-human transmission of the responsible agent.

Human aeromonas infections: a review of the literature and a case report of endocarditis

Our patient, with cirrhosis and chronic renal failure, represents an example of the susceptibility of a compromised host to Aeromonas infections. This patient, however, differs from previously reported cases in at least two important aspects. First, it is possible that her portal of entry was a fresh A-V fistula puncture site rather than an intestinal site. The temporal relationship of exposure to flood water prior to the onset of sepsis lends support to this possibility. Epidemiologic investigation of the dialysis center failed to reveal Aeromonas isolates from cultures of the water supply, machinery, or other patients. Second, this case is unique in that our patient developed a destructive aortic valve endocarditis resulting in valvular perforations and acute aortic insufficiency. Furthermore, this infection was initiated on what appears to have been a previously normal valve. Based on a review of the literature and the virulence demonstrated by A. hydrophila in our patient, we conclude that organisms of the genus Aeromonas are capable of inducing serious human infection. Such infections are more likely to occur in compromised hosts. A. hydrophila has accounted for the majority of reported infections.

Endocarditis due to Hemophilus aphrophilus: report of a case with possible transmission from dog to man

A 44-year-old man was treated for bacterial endocarditis due to Hemophilus aphrophilus. The characteristics of the organism are reviewed, along with other cases of endocarditis. There is an association of this organism with dogs and a potential for transmission from this source to man.

Infective endocarditis following human-to-human enterococcal transmission: a complication of intravenous narcotic abuse

Two heroin addicts, husband and wife, who shared injection paraphernalia extensively, developed enterococcal endocarditis within six weeks of one another. The etiologic organisms were of the same subspecies and had identical antibiotic susceptibilities and biochemical profiles. The clinical, epidemiologic, and bacteriologic data strongly suggest human-to-human transmission of the pathogen.

Outbreaks of Serratia marcescens infections in a cardiothoracic surgical intensive care unit

An outbreak of infections with pigmented Serratia marcescens involving 3 patients in a cardiothoracic surgical intensive care unit is reported. A respirator is thought to have been the source of pneumonia in 2 patients, and fomite spread from 1 of these is considered responsible for the induction of fatal endocarditis in the third patient. This outbreak demonstrates the rapid dissemination of a bacterial strain within the unit, several methods of dissemination, the wide variation in apparent virulence of the organism, the alterations of antibacterial host defense which made bacterial disease possible and which determined the site of infection, and the difficulties of adequate therapy. The third patient is the seventh reported with serratia infection of a prosthetic heart valve.