Infections In Hospitalized Patients Research Articles

Advances in the prevention and treatment of cytomegalovirus infection in hospital patients

The incidence of cytomegalovirus (CMV), a common pathogen for hospital patients, can be reduced by providing virus-free blood products. The virus can also be transmitted via solid organ allografts and the efficacy of matching donor and recipient for improving overall patient survival needs formal evaluation. Patients at risk of future disease can be detected by surveillance cultures, whose prognostic value is good for bone marrow transplant recipients; formal evaluation in other groups of patients is required. This is particularly important now that ganciclovir and foscarnet are licensed for the therapy of life-threatening CMV infections and other therapies are available on an investigational basis. Resistance to ganciclovir has been described and is likely to be an increasing problem. Placebo-controlled trials have shown that prophylaxis with α-interferon, immunoglobulin or high-dose acyclovir can significantly reduce CMV infection and CMV disease.

The epidemiology of infections in intensive care units

This report identifies some of the risk factors underlying the acquisition of hospital infections in patients admitted to Intensive Care Units (ICUs). Infection rates vary in different institutes and in different types of ICUs. Patients are particularly prone to septicaemia and respiratory infections and the underlying risk factors are frequently related to poor invasive techniques or contaminated equipment used in supportive therapy. In trauma patients, wound sepsis is common and polymicrobial sepsis is a major problem. Patients in ICUs are temporarily immunocompromised and are at risk from acquiring multiply antibiotic resistant gram negative bacilli. The majority of these are of an endogenous nature and necessitate the empirical use of antibiotics. The misuse of antibiotics however often leads to the selection of difficult to treat gram negative bacilli. Antibiotic usage in ICUs should be strictly controlled and used appropriately, preferably after appropriate microbiological specimens have been collected.

Augmentin (intravenous then oral) compared with cefuroxime followed by cephalexin for chest infections in hospitalised patients

SummaryAugmentin and cefuroxime were compared in the treatment of chest infections in hospital patients in a multicentre study. One hundred and six patients were randomly allocated to 48 hours treatment with intravenous Augmentin, (amoxycillin 1g + clavulanic acid 200mg), every eight hours. Sixty eight patients received cefuroxime (750mg) intravenously every eight hours. Patients receiving intravenous Augmentin were then given five days oral treatment with Augmentin. Patients receiving cefuroxime were subsequently given five days oral treatment with cephalexin. For severely ill patients, the intravenous phase of treatment was extended from 48 to 96 hours.There was no significant difference in the numbers of patients showing a good overall response to the two therapies at 48 hours. However, at Day 7 significantly more patients were clinically improved or cured after receiving Augmentin as opposed to those taking cefuroxime/cephalexin.There were no significant differences between treatment groups when analysed by indication or by key sign or symptom.At the start of treatment bacterial organisms were isolated from the sputum of 29/87 (33 per cent) of patients who received Augmentin and from 19/48 (40 per cent) of patients producing sputum who received cefuroxime. Both treatment regimens proved effective against the organisms isolated at the start of treatment. At the end of treatment all of these organisms had been eradicated by Augmentin and 91 per cent had been eradicated by the cefuroxime/cephalexin regimen.Both treatments were well tolerated, with no significant difference between treatments in the small number of adverse events noted.Augmentin and cefuroxime have been shown to be similarly effective and well tolerated treatments for chest infection. In addition, it is shown that Augmentin has advantages in terms of speed of response and it is available as both intravenous and oral formulations. Thus, Augmentin would be a suitable first choice antibiotic for the treatment of lower respiratory tract infections.

Environmental factors in nosocomial infection-a selective focus.

For many years attempts to control nosocomial infection consisted of programs to measure and then reduce the number of microorganisms present in the hospital environment. Recently, however, investigation of documented episodes of infection in hospital patients or personnel has been emphasized, and the role of routine microbiologic monitoring has been minimized. Further improvements in infection control will require a better understanding of the relative importance of objects in the animate and inanimate environment as reservoirs and vectors for infection rather than development of newer and better ways to culture the environment.

An investigation into the incidence and sources of klebsiella infections in hospital patients

Coliforms isolated from infections over a period of 22 months were examined and 16% were shown to be klebsiellas. The biochemical reactions and serotypes of these klebsiellas were determined and the relationship between species, serotype and type of infection investigated. Although no obvious outbreaks of infection occurred during this period a number of clusters of isolations of the same serotype of klebsiella were found. Using an enrichment method for the isolation of klebsiellas from faeces, sero and bacteriocin typing, and the examination of ten colonies, it was demonstrated that half of the patients carried a klebsiella of the same type in the bowel as caused the infection.

Predominance of certain klebsiella capsular typesin hospitals in the United Kingdom

Summary Three hundred and fifty-seven strains of Klebsiella aerogenes sent from 357 different patients in 20 United Kingdom hospitals were capsular typed. Serotypes K21, K2 and K9 were most frequent and accounted for 42·0, 16·5 and 7·3 per cent respectively of all strains. A significantly large proportion of hospitals (14 out of 20) had isolates of K21, and this serotype, with K2, most commonly caused clusters of infection of four or more patients in individual hospitals within a four-week period. It is suggested that the prevalence of types K21, K2 and K9 reflects some unidentified epidemiological advantage that declares itself in clusters or epidemics of colonisation and infection in hospital patients.

Secondary respiratory infection in hospital patients: effect of antimicrobial agents and environment.

A prospective study of 358 medical and 234 postoperative patients with clinical evidence of secondary chest infection showed that previous administration of antimicrobial agents greatly reduced the chance of obtaining a clear-cut laboratory report. In patients with radiographical evidence of pneumonia this led to a fourfold decrease in the overall rate of isolation of potential pathogens. Furthermore, 81 diverse "coliforms" were isolated from 258 medical and surgical patients who had received previous antimicrobial therapy while only four coliforms (all Escherichia coli) were isolated from 334 untreated patients. Thus the general hospital environment on its own seemed to have a negligible influence in promoting the growth of coliform flora in sputum. Any unique effect of underlying disease in this regard was masked by that of previous therapy. Finally, the results raised the possibility that previous antimicrobial therapy might have increased the risk of secondary pneumonia in hospital patients.

Respiratory Viral Infections in Hospital Patients with Chronic Bronchitis: Observations during Periods of Exacerbation and Quiescence

All patients admitted to the pneumology department with chronic bronchitis between November, 1968, and July, 1969, were included in the survey. During periods of exacerbation diagnosis of viral infection was based on virus isolation, associated or not with seroconversion. Outside the periods of exacerbation the survey was confined to determining seroconversion on serum samples taken every month. Forty-nine exacerbations were observed. A diagnosis of viral infection was made in 31 cases (63.3 percent) by virus isolation and/or seroconversion. Seroconversion alone detected 21 of 37 cases (56.8 percent). Isolation alone detected a virus in 15 of 29 cases (51.7 percent). In 10 of these 29 cases (34.4 percent), moreover, viruses were isolated in urine during the first few days of the exacerbation. The viruses most frequently involved were influenza and parainfluenza. The ratio of association between viral infections and exacerbations is high; the seroconversion study during exacerbations and at other times revealed a great difference, 58.3 percent to 3.7 percent.

Statistical analysis of staphylococcal infection in hospital patients in relation to use of antibiotics and other factors.

SUMMARYWhen staphylococcal strains from hospital patients are plotted in a frequency curve according to the size of the growth-free zone in a disk test for sensitivity to penicillin-G, this curve is trimodal. This implies that, besides the sensitive, there are two populations of resistant staphylococci: the moderately and the highly resistant, In a hospital-wide survey of coagulase or mannite positive staphylococci isolated in North Carolina Memorial Hospital between October 1964 and October 1965 it was inferred that: (1) there was a statistically highly significant difference between the distributions of the moderately and the highly resistant strains over duration of hospital stay prior to the time of isolation; (2) the highly resistant strains were seldom introduced from outside; and (3) there was no significant association between use of penicillin-G by a patient harbouring a strain and the frequency with which such a strain was found to be highly resistant to this drug. The latter finding is in contrast to significant associations found when the penicillin resistance is moderate, or when the drug used is other than penicillin-G. It is concluded that a fall in the incidence of staphylococcal strains highly resistant to penicillin-G in patients who did not receive other antibiotics may well be a valid index of the efficacy of programmes to control hospital infection. If so, there is a practical merit in adopting the routine of distinguisning between two groups of penicillin-resistant staphylococci, which behave, epidemiologically, as two distinct bacterial populations.

A Survey of Intestinal Protozoa among Children and Adults in Los Angeles

A number of reports have been published from California which give the incidence of intestinal protozoan infection in hospital patients and in groups examined in medical practice who were suspected of having gastro-intestinal symptoms (see Barrow (1924), Kofoid (1926), Kessel and Mason (1930)). More recently, two reports have appeared from non-clinical groups, one by Johnstone, David and Reed (1933) on a group of prisoners from San Quentin and one by Iverson and Johnstone (1937) on food handlers from San Francisco. The present report records the results of examination2 of 2016 individuals, examined for purposes of survey alone, these persons exhibiting no gastro-intestinal symptoms for which they sought medical examination. They belong to three groups: (1), 585 adults seeking work as kitchen employees in the Los Angeles County Hospital; (2), 753 adult clinic patients seeking medical attention for conditions other than gastrointestinal in nature; (3), 678 children from a Los Angeles City Juvenile Detention Home.