The changing face of infection: a comparative review of admissions to a regional infection unit over three decades.

BACKGROUND AND AIMS: Our group previously published retrospective analyses of 12 months of admissions to the Grampian Regional Infectious Diseases Unit from 1980-81 and from 1991. This study aimed to collect data in 2001 and to compare annual admission numbers, diagnoses, duration of stay and outcome in 1980-81, 1991 and 2001. METHODS: Data on all admissions was collected prospectively throughout 2001. This was compared with the previously published data. RESULTS: Total admissions rose from 605 in 1980-81 to 900 in 1991 and to 1152 in 2001. Sixty one percent of admissions in 1980-81 were confirmed as having infection compared to 72% in 1991 and to 83% in 2001. The most common reason for admission in 2001 was skin and soft tissue infection, but this was only the ninth commonest reason in 1981. Mean length of stay fell from 9.6 days in 1980-81 to 7.4 days in 1991 and to 5.5 days in 2001. The mortality rate fell from 3.1% in 1981 and 1991 to 1.0% in 2001. CONCLUSIONS: This study demonstrates significant changes in type, number and outcome of admissions to a regional infection unit. We discuss possible reasons for these changes.

A qualitative study of determinants of patient behaviour leading to an infection related hospital admission.

Objectives To describe and understand the determinants of patients' behaviours surrounding admission to hospital for an acute infective episode Method Patients admitted to the infection or acute medicine admission units of a major Scottish teaching hospital and commenced on antibiotic therapy after admission were included. Semi-structured face-to-face interviews were conducted using a pre-piloted interview schedule guide that focused on gathering information about patient behaviours and experiences prior to admission to hospital with an acute infection. Interviews were audio-recorded, transcribed verbatim and analysed using the Framework Approach. Emerging themes were matched to the Theoretical Domains Framework of behavioural determinants. Results Twenty-one patients consented to participate and 18 transcripts were suitable for analysis. The most common infections were those of the skin, soft tissue and respiratory tract. From the patients' perspectives, behavioural determinants that appeared to impact their admission to hospital were principally their knowledge, beliefs of consequences, the environmental context and resources (mainly out-of-hours services), social influences and their own emotions. Determinants such as knowledge of the signs and symptoms, beliefs of consequences and environmental context were facilitators of health seeking behaviours. The main barriers were a lack of awareness of consequences of infection potentially leading to delayed admission impacting infection severity, stay in secondary care and resource utilisation. Conclusions This study has shown that any initial patient-centred intervention that is proposed to change patient behaviour needs to be based on behavioural determinants emerging in this research. The intervention may include aspects such as patient education on resources available out-of-hours and ways to access the healthcare system, education on recognising signs of infection leading to prompter treatment and positive reinforcement for patients who present with recurrences of infection.

Disseminated disease due to Mycobacterium avium complex in AIDS.

We retrospectively analysed 46 cases of disseminated infection with Mycobacterium avium complex (MAC) within a cohort of 702 HIV-infected patients in Edinburgh. Clinical features were compared with case-matched controls (AIDS cases without disseminated MAC), and survival and progression times were controlled for confounding variables that influence survival. Disseminated MAC was diagnosed antemortem in 18% of AIDS patients, and was the AIDS-defining diagnosis in 6% of all AIDS cases. Concomitant colonization of respiratory and gastrointestinal tracts was common (61% and 48%, respectively). In 58% of cases, CD4+ counts were < 10 cells/mm3 (median 6 cells/mm3). Weight loss, anaemia, leucopenia, and elevated liver transaminases and alkaline phosphatase were significantly more common among cases than controls. Therapy was given in 74%, and not tolerated in 32%. Following AIDS diagnosis, disseminated MAC incidence was 14% at one year, 25% at 2 years and 36% at 3 years. Median survival after disseminated MAC diagnosis was 6 months, with shorter survival in untreated cases. However, overall survival from AIDS diagnosis was not significantly different between patients who did or did not develop disseminated MAC. Disseminated MAC contributes significantly to AIDS morbidity, and its incidence increases with prolonged AIDS survival. Although survival following diagnosis is short, the development of disseminated MAC in AIDS probably does not affect overall survival. In cohorts with a low incidence, an alternative to prophylaxis might be surveillance and early diagnosis.

Audit of an antibiotic policy and microbiological investigations for treating bacteraemia in a large teaching hospital.

An audit of different approaches to guide empirical therapy in 78 cases of bacteraemia revealed poor utilisation of the antibiotic policy with resulting inadequate (P=0.005) or excessive (P<0.00001) antibiotic treatment and a trend to increased mortality. Eighty-seven percent of blood cultures were positive on Gram-stain within 24 h but streamlined therapy was still judged excessive in 27%. The results show poor utilisation of an up-to-date antibiotic policy but confirm its potential benefits and the ability of traditional culture methods to guide antibiotic therapy in a useful time-scale.

Duration of intravenous therapy and hospital stay according to choice of empirical antimicrobial treatment for community-acquired respiratory infection.

A review of patients admitted to medical wards with respiratory infection was undertaken to look for differences in duration of intravenous (IV) therapy and length of patient stay based on the class of IV antimicrobial used in treatment. Data was analysed from 231 patients with community-acquired respiratory infection who were treated empirically for at least 24 h with either an IV cephalosporin (146 patients) or an IV penicillin or macrolide (85 patients). The severity of illness and indication for IV treatment was similar in each group. Those treated with a cephalosporin received IV therapy for a significantly longer period (mean = 4.44 days, SD = 2.6) than those given a penicillin or macrolide (mean = 3.3 days, SD = 1.8): P < 0.001. Patient stay was significantly longer in the cephalosporin group (mean = 11.6 days, SD = 10.4) than the penicillin/macrolide group (mean = 9.4 days, SD = 6.3): P = 0.04. These differences are most readily accounted for by the absence from the hospital formulary of a third generation oral cephalosporin, a drug that might be regarded as an obvious form of follow-on therapy in patients treated empirically with an injectable cephalosporin.

Nosocomial infections in patients with HIV disease.

Throughout the AIDS epidemic, nosocomial infection in the patient with HIV disease has presented a constant problem--not only for the hospitalized patient but also for the clinic attender. The nosocomial spread of multidrug-resistant tuberculosis has emphasized the need for effective control of infection measures in dealing with the immunodeficient. Increased recognition of nosocomial bacterial pneumonias has raised questions about the place, if any, of antimicrobial prophylaxis in preventing Gram-negative and Legionella infection. The use of long-term indwelling venous catheters for the administration of parenteral therapy is associated with an increased risk of nosocomial bloodstream infection--particularly from staphylococci and Pseudomonas spp. Evidence now exists for the nosocomial spread of opportunistic infections, including Cryptosporidium parvum, Mycobacterium avium complex and Pneumocystis carinii. The delay between exposure and diagnosis, the atypical presentation of infections such as tuberculosis and repeated hospital admissions of AIDS patients can combine to confuse the issue with the result that a nosocomial infection may be mis-classified as community-acquired. It seems likely that the burden of nosocomial infection in HIV disease is continually underestimated.

An audit of the clinical features and use of antimicrobials in adult diarrhoea.

We reviewed the case records of 128 adult patients hospitalized with diarrhoea. A relevant stool pathogen was isolated from 45, a diagnosis of culture-negative or non-specific gastroenteritis (NSGE) was made in 40 and the remaining 43 patients had no enteric infection. A history of fever or bloody stools was more common in those with culture-positive gastroenteritis than it was in those with NSGE or other diarrhoeal illness. The mean duration of diarrhoea prior to admission was significantly shorter in those with all forms of gastroenteritis than it was in the remainder. Epirical treatment with ciprofloxacin was commenced in 46% of all cases of gastroenteritis, of which 51% were found to have a relevant pathogen on stool culture. Patients with NSGE were just as likely to be treated with ciprofloxacin as those who were subsequently found to have culture-positive gastroenteritis. A history of abdominal tenderness or bloody stools did not discriminate for treatment with empirical ciprofloxacin in any patient group. Patients with positive stool cultures were more likely to be given ciprofloxacin if they were febrile but the same was not true for the other patients. In the patients reviewed, a significantly higher proportion of those with culture-positive diarrhoea presented with a history of fever or bloody stools. Despite this, the empirical use of ciprofloxacin in suspected infective gastroenteritis appeared to be only partially guided by the clinical features.

Salmonella enteritidis urinary infection associated with polycystic renal disease.

Extraintestinal infection from non-typhoidal Salmonellae is uncommon and infection in the urine is particularly rare. We report a patient with polycystic renal disease and diabetes mellitus who developed a urinary infection due to Salmonella enteritidis following presumed enteric infection. Isotope white cell scanning demonstrated active infection in the left kidney.

Recurrent post-infective Henoch-Schönlein syndrome: a genetic influence related to HLA B35?

The clinical features, laboratory findings, infection stimuli and HLA phenotypes of five young adults with recurrent episodes of Henoch-Schönlein syndrome (HSS) are reported. We define recurrences as the reappearance of the characteristic purpuric rash and associated symptoms more than 8 weeks after the onset of the original episode of purpura. All patients had documented evidence of a bacterial or viral infection before one or more of the relapses, the periods between which varied from 1 to 13 years. Four of our five patients possessed the HLA B35 phenotype and two of these four patients were also HLA B18 antigen positive. Those with the HLA B35 haplotype had recurrent episodes of purpura with nephritis triggered by minor pharyngeal (viral or bacterial) infections. The HLA B35 haplotype has a frequency of 4% in the indigenous Scottish population and has previously been linked with single episodes of the Henoch-Schönlein syndrome with nephritis in German, Slavic and French patients. It has not previously been related to recurrent episodes of the syndrome. We postulate that patients who are HLA B35 positive may be genetically more susceptible to recurrent episodes of HSS with nephritis, stimulated by a heterogeneous group of infective stimuli and resulting in a protracted illness with significant renal involvement.

Epidemiology and outcome of HIV infection in North-East Scotland (1985-1997).

OBJECTIVE: to assess the epidemiology of HIV infection in North-East Scotland. METHODS: retrospective casenote review of all HIV-infected patients who have had contact with the Infection Unit in Aberdeen. RESULTS: one hundred and forty-two HIV-infected patients were treated between April 1985 and December 1997. The risk behaviour related to the acquisition of the HIV infection was: 56 (39%) homosexually infected, 45 (32%) heterosexually-infected, 34 (24%) injecting drug users (IDUs), and seven (5%) blood products or not known. Sixteen of the 45 (36%) heterosexually-infected patients were native to Africa and 16 of the 34 (31%) IDUs were prisoners in Peterhead prison at the time of referral. Fifty-two (37%) of the cohort continue to attend the Infection Unit, 41 (29%) have relocated, 40 (28%) have died and nine (6%) have been lost to follow-up. The ratio of heterosexual:homosexual men:IDUs changed significantly between the first 7 years (12:21:25) and the second 6 years (33:35:9) of the review, with significantly more patients being infected through heterosexual contact and fewer infected by IDU in the second period-P<0.001. The median AIDS survival was 17 months. Survival was significantly longer in those patients who took anti-retroviral therapy (median = 20 months) than in the patients who opted not to take anti-retroviral therapy (median = 11 months)-P<0.01. CONCLUSIONS: Although homosexual contact represents the commonest risk group for HIV infection in this region, the number of heterosexually-infected patients has increased significantly in the last 5 years. Temporary residents account for one-third of the HIV-infected population cared for in NE Scotland. Almost half of those lost to follow-up have returned to Africa or been released from prison. The introduction of anti-retroviral therapy has resulted in a dramatic improvement in AIDS survival in our cohort as it has done elsewhere.

Presenting clinical features and C-reactive protein in the prediction of a positive stool culture in patients with diarrhoea.

OBJECTIVES: To devise a scoring system by which clinical features and C-reactive protein (CRP) can be used to predict a positive stool culture in patients admitted with acute diarrhoea. METHODS: One hundred and thirty-two patients admitted to the Regional Infection Unit with diarrhoea thought to be due to bacterial gastroenteritis were included. Clinical features, CRP and outcome of stool culture were recorded, together with the final diagnosis. RESULTS: Forty-one patients had bacterial gastroenteritis characterized by the isolation of a bacterial enteropath (BGE). Sixty-three patients had non-specific gastroenteritis, defined as more than three loose stools per day with no bacterial enteropath isolated (NSGE). In 28 patients another diagnosis was made (Others). More of the patients with BGE (91%) had abdominal pain as compared with those with NSGE (67%) and Others (61%) (P=0.01). The mean duration of symptoms was longer in the Others group (6.14 days) as compared with patients with BGE (3.29) and NSGE (3.25) (P=0.01). The mean CRP was significantly higher in those with BGE (113.9mg/l) and Others (116.9mg/l) as compared to the NSGE patients (38.9mg/l) (P=0.001). A scoring system was devised which incorporated the presence or absence of abdominal pain (+10 or 0), the duration of symptoms (-10, for 5 or more days, 0 for less than 5 days of symptoms) and the CRP (CRP<50=0, CRP>50=5). A score of 15 or more predicted 79% of patients with BGE, while a score of <15 predicted 87% of those with NSGE and 86% of those with another diagnosis. CONCLUSIONS: This simple scoring system may be useful in predicting the positivity of stool culture, and therefore may be helpful in targeting those small number of patients who require antimicrobial therapy after hospital admission. We would not, however, favour reliance on this scoring system alone to choose whom to treat with antimicrobials.

Clinical predictors of azole resistance, outcome and survival from oesophageal candidiasis in AIDS patients.

A retrospective review of AIDS-related oesophageal candidiasis was undertaken to identify clinical features helpful in predicting response to azole therapy and patient survival. Patients who had received daily azole prophylaxis against candidiasis were significantly less likely to respond to azole therapy than those who had not (P < 0.001). Patients who had lost > 5% of their body weight in the 2 months before oesophageal candidiasis were less likely to respond to azoles than the others (P < 0.001). Amongst those who had not received daily azoles, patients with a CD4+ cell count < 25/mm3 were less likely to respond to azole treatment (P = 0.05). The median survival beyond oesophageal candidiasis was 18 months. Survival from oesophageal candidiasis was significantly poorer for patients who did not respond to azole therapy but AIDS survival did not differ between azole responders and non-responders. Non-responders who had been taking daily azole prophylaxis had the poorest survival (median = 4 months).

Venous thrombosis in HIV infection.

Previous reports indicate that venous thrombosis is an infrequent problem in patients with HIV infection. Despite this, various HIV-related factors have been proposed as potentially thrombogenic and an HIV-related hypercoagulability has been suggested. At the present time, there exists no consensus of opinion regarding prophylaxis against venous thrombosis for hospitalized patients with HIV. This article aims to provide an overview of venous thrombosis in HIV infection with particular reference to published and personal evidence for possible risk factors and their implications for prophylaxis.

Clinical features, outcome and survival from cerebral toxoplasmosis in Edinburgh AIDS patients.

Nineteen cases of cerebral toxoplasmosis (CTOX) are reported from a group of Edinburgh AIDS patients. All patients were severely immunodeficient at the time of presentation with CD4 count < 50 cells/mm3. Thirteen patients had suffered a previous AIDS-defining illness. In Edinburgh, CTOX has developed in 48% of patients who are seropositive for toxoplasma and have a CD4 count < 50 cells/mm3. It is estimated that at least half of the toxoplasma seropositive patients will develop CTOX if they survive for 21 months after reaching a time in their illness when the CD4 count = 50 cells/mm3. The incidence of CTOX in toxoplasma-seronegative patients with a CD4 count < 50 cells/mm3 is 1.3%. All patients showed improvement on treatment and there was no correlation between clinical or radiological features and patient survival. Those patients unable to tolerate first choice anti-toxoplasma therapy had a significantly shorter survival than the remainder but there was no single therapeutic regimen which conferred a survival advantage. Eighteen patients had died at the time of study and the median survival following diagnosis of cerebral toxoplasmosis was 10 months (range 3-38 months). Postmortem examination of the brain was available in 8, 4 of whom had concomitant cerebral lymphoma. The survival from AIDS or CD4 count = 50 cells/mm3 did not differ significantly between those with treated CTOX and a control group who had no toxoplasma infection, suggesting that treatment is reasonably effective. CTOX is a disease associated with severe HIV-related immunodeficiency and, in those with a CD4 count < 50 cells/mm3, occurs more than 35 times as frequently in toxoplasma-seropositive than toxoplasma-seronegative patients. Treatment is effective but the outcome of treated disease cannot be predicted from presenting clinical or radiological features. Concomitant space-occupying cerebral pathology is evident in 50% of post-mortem examinations.

Antimicrobial treatment of fish tank granuloma.

Three patients with fish tank granuloma of the hand and forearm are reported. Each patient was treated with antimicrobial regimes which have rarely or never been previously used in this condition. Two patients responded well to treatment, one who received ciprofloxacin plus clarithromycin and another who was given clarithromycin plus ethambutol. The third patient received six different antimicrobial regimes before responding to a combination of rifabutin and ciprofloxacin. Our experience suggests that there now exist a number of effective alternatives to antimicrobials which have been traditionally used in the treatment of cutaneous Mycobacterium marinum infection.

Stridor in patients with HIV infection.

The immunodeficiency which results from HIV infection is associated with a range of opportunistic infections and tumors which may present with the symptoms of upper airways disease. This paper presents three cases of stridor from different causes in patients with HIV infection, all of whom recovered following treatment. The management of this problem requires consideration of the likely aetiology which, in those with advanced immunodeficiency, includes bacterial and fungal laryngitis and epiglottitis as well as rapidly growing laryngeal tumours. Recommendations for the treatment of those with HIV infection who present with severe or rapid-onset stridor should include a combination of aggressive airway intervention and broad-spectrum antibacterial and antifungal agents. Laryngeal biopsy for histology and culture is particularly important for those patients who fail to respond to the aforementioned treatment.

Alcoholism, hyponatraemia and central neurological damage: more than pontine myelinolysis?

Three patients with alcoholism and severe hyponatraemia are described. Permanent neurological damage occurred in each case with cerebral, cerebellar or pontine damage from infarction or haemorrhage following correction of the biochemical disturbance. No patient developed Central Pontine Myelinolysis (CPM), the condition usually associated with profound hyponatraemia and its correction.

Neisseria meningitidis W135 pneumonia with sepicaemia in a nonogenarian.

Neisseria meningitidis infection is generally considered a disease of children or young adults, classically presenting as meningitis or sepicaemia. This infection is rare but recognised in the elderly. We present the case of a nonogenarian with meningococcal pneumonia and sinusitis with bacteraemia caused by N.meningitidis W135 a rare serogroup. We therefore thought this unusual situation of interest and worthwhile reporting.

Opportunistic group G streptococcus infection of both prosthetic knee joints.

A case of polyarticular sepsis from group G streptococcus is described in a patient with rheumatoid disease and decubitus ulcers. This is a rare condition which is often associated with a mosaic of predisposing factors and requires prompt and aggressive antimicrobial therapy.

Raw egg ingestion and salmonellosis in body builders.

Four patients with Salmonella enteritidis infection are reported. All were body builders who regularly consumed substantial quantities of raw eggs. They presented with a severe febrile illness and diarrhoea--presumably reflecting a large bacterial inoculum. Advice regarding the potential hazards of raw egg ingestion has been repeatedly issued by the Department of Health--but this report highlights the fact that this practice continues in spite of this. The epidemiology of S. enteritidis infection in relation to raw egg ingestion is discussed.