Culture negative endocarditis: data from the national survey in Slovakia

Millar et al in their interesting review discussed culture negative endocarditis.1 The mainstay of diagnosis of infective endocarditis is still conventional blood culture; however, blood culture may be negative in 1%–79% of all cases. The incidence of culture negative endocarditis has been increasing. This could be for a number of reasons. Prosthetic heart valves are prone to infection and in many of these cases the culture is negative. Many …

Millar et al in their interesting review discussed culture negative endocarditis. 1 The mainstay of diagnosis of infective endocarditis is still conventional blood culture; however, blood culture may be negative in 1%-79% of all cases. The incidence of culture negative endocarditis has been increasing. This could be for a number of reasons. Prosthetic heart valves are prone to infection and in many of these cases the culture is negative. Many aetiological agents causing infective endocarditis may be fastidious in nature, such as the HACEK group of organisms 2 or unusual and require specialised microbiological techniques.
In univariate analysis comparing all cases (180) to culture negative (35 cases), prior cardiosurgery within two weeks (p<0.045), probable endocarditis (p<0.04) according to Duke's criteria, 4 and emboli (p<0.001) were more frequently observed among the group with culture negative endocarditis, and prior dental surgery (p<0.03) and a definitive diagnosis (p<0.045) among all cases of endocarditis (see table 1). In addition multivariate analysis (STAT ADV computerised package of the postgraduate medical school) was performed. The only significant risk factor for culture negative endocarditis in multivariate analysis was presence of complications. The odds ratio was 2.45 (confidence interval 0.95 to 2.35) in the group with culture negative endocarditis, which was 2.45 times higher than in culture positive endocarditis.
Interestingly mortality was lower in culture negative endocarditis than among all cases (24.5% v 44.4%,p<0.001). Millar et al in his excellent review analysed reasons for culture negative endocarditis. We found according to our experience one more risk factorprior cardiac surgery. Probably, those undergoing cardiac surgery and receiving antibiotic prophylaxis (first generation cephalosporins/cefazolin in Slovakia) have lower death rates in endocarditis due to protective effect of antimicrobials for occurrence of infection. Ethical, professional, and legal obligations in clinical practice We wish to applaud Mr Gore on conducting sessions and writing about ethical, professional, and legal obligations in clinical practice. [1][2][3] It is an area in which most doctors fail to get training at an earlier stage, and there is a case for other specialties to take heed from Gore's series and conduct such educational exercises in their hospitals.
We agree with Gore that doctors tend to underestimate how willing people are to talk about their own death 3 and, in fact, their resuscitation status. As doctors we tend to assume that this discussion with patients (where feasible) would upset them enormously and hence the reluctance to discuss it with them.
To find an answer to this dilemma, we conducted an interview based study in our district general hospital, where 70 inpatients on medical wards were interviewed to assess their knowledge of cardiopulmonary resuscitation and their views on getting involved in their "not for resuscitation" (NFR) decision. The group had equal number of male and female patients and equal number of patients below and above the age of 70 years. The results were very interesting and showed that majority (∼71%) of the hospital inpatients wished to get involved in the discussion related to their NFR decision. This view was similar among young and old patients. This sends a strong message that ethically we ought to involve mentally competent patients in their NFR decisions if the latter so wish.
We disagree with Gore that resuscitation be offered if it is specifically requested by a patient even if a successful resuscitation is unlikely. 3 In patients in whom cardiopulmonary arrest clearly represents a terminal event in their illness, attempted resuscitation might be considered inappropriate. Neither patients nor their relatives can demand treatment that the health care team judges to be inappropriate. 4 There are situations where medical reality and patient's expectations in relation to their illness and NFR decisions do not match. 5 In situations like these the healthcare team has the moral and legal responsibility to help their patients reach a decision in their best interest.

Department of Medicine for the Elderly, Wrexham
Maelor Hospital, Wrexham LL13 7TX, UK; dralokjain@netscapeonline.co.uk Author's reply I welcome the comments of Dr Jain and his colleagues. The apposite study which they conducted at Wrexham Maelor Hospital demonstrates the desire among patients, young and old, for involvement in NFR decisions. As doctors we must confront our own unease at discussing matters of resuscitation and death with patients. I accept the authors' reservations about my endorsement of compliance with a patient's wish for cardiopulmonary resusciation in all cases. In many such cases cardiopulmonary resusciation would be medically inappropriate, and it is indeed the responsibility of the healthcare team to counsel the patient accordingly. Nevertheless the series of discussion articles was geared towards education for junior medical staff, and I chose to keep the guidelines straightforward with an emphasis on patient autonomy. Certainly in any such situation one would expect a more senior member of the healthcare team to identify and address that mismatch between medical reality and patient/relative expectation. Counselling might then be offered in the hope of reaching consensus on the suitability of a NFR decision.

Intraoperative glove perforation
We read with interest the paper by Thomas et al concerning single versus double gloving in protection against intraoperative skin contamination from glove perforation. 1 We note that one of the methods used to detect glove perforation was the water leak method. Although we accept that the water leak test is an acceptable method we believe that it is not as sensitive as the electrical conductance test as demonstrated by Sohn et al. 2 Interim results from an ongoing study yielded 211 sterile and non-sterile gloves used during venepuncture or wound closure in our emergency department. We identified nine glove perforations with the water leak test and 22 with the electrical conductance test. All water leak positives were also electrical conductance test positive. This study supports the work by Sohn et al. We believe that Thomas, Agarwal, and Metha may have underestimated the incidence of glove perforation in their study group.