Allergy in the elderly: A case note review of referrals to an adult allergy clinic.

The UK population is ageing and we can expect more referrals to allergy clinics for this age group. 16% of patients to our clinic are aged >60. Compared to younger patients, 3 times as many referrals were for angioedema. Overall, allergy was excluded in 79% of cases. 15% were diagnosed with previously unrecognised allergies, while allergic disease was confirmed in 6%, enabling optimised management. While the differential diagnosis of allergic conditions is wider in older people, assessment in the allergy clinic is helpful and adds value.

Summer indoor heat exposure and respiratory and cardiovascular distress calls in New York City, NY, U.S.

Most extreme heat studies relate outdoor weather conditions to human morbidity and mortality. In developed nations, individuals spend ~90% of their time indoors. This pilot study investigated the indoor environments of people receiving emergency medical care in New York City, NY, U.S., from July to August 2013. The first objective was to determine the relative influence of outdoor conditions as well as patient characteristics and neighborhood sociodemographics on indoor temperature and specific humidity (N = 764). The second objective was to determine whether cardiovascular or respiratory cases experience hotter and more humid indoor conditions as compared to controls. Paramedics carried portable sensors into buildings where patients received care to passively monitor indoor temperature and humidity. The case-control study compared 338 respiratory cases, 291 cardiovascular cases, and 471 controls. Intuitively, warmer and sunnier outdoor conditions increased indoor temperatures. Older patients who received emergency care tended to occupy warmer buildings. Indoor-specific humidity levels quickly adjusted to outdoor conditions. Indoor heat and humidity exposure above a 26 °C threshold increased (OR: 1.63, 95% CI: 0.98-2.68, P = 0.056), but not significantly, the proportion of respiratory cases. Indoor heat exposures were similar between cardiovascular cases and controls.

Guidelines for the prevention of sepsis in asplenic and hyposplenic patients.

Asplenic or hyposplenic patients are at risk of fulminant sepsis. This entity has a mortality of up to 50%. The spectrum of causative organisms is evolving as are recommended preventive strategies, which include education, prophylactic and standby antibiotics, preventive immunizations, optimal antimalarial advice when visiting endemic countries and early management of animal bites. However, there is evidence that adherence to these strategies is poor. Consensus-updated guidelines have been developed to help Australian and New Zealand clinicians and patients in the prevention of sepsis in asplenic and hyposplenic patients.

Neuropsychological presentation and adaptive skills in high-functioning adolescents with visual impairment: A preliminary investigation.

Studies in infants and young children with congenital visual impairment (VI) have indicated early developmental vulnerabilities, conversely research with older children and adults have highlighted areas of cognitive strength. A minimal amount is known, however, about the possible combination of strengths and weaknesses in adolescence, and this present study therefore aims to explore the neuropsychological presentation and adaptive behavior profile in high-functioning adolescents with congenital VI. Participants completed a battery of commonly used neuropsychological measures assessing memory, executive function, and attention. The measures utilized focused on auditory neuropsychological function, because only subtests that could be completed with auditory administration were suitable for this sample. Parents completed standardized measures of adaptive behavior, executive function, and social communication. Compared to aged-based norms for normal sight, adolescents with VI demonstrated strengths in aspects of working memory and verbal memory. Furthermore, performance across the neuropsychological battery was within or above the average range for the majority of the sample. In contrast, parent-report measures indicated areas of weakness in adaptive functioning, social communication, and behavioral executive functioning. Overall, this study provides preliminary evidence that relative to fully sighted peers, high-functioning adolescents with VI present with an uneven profile of cognitive and adaptive skills, which has important implications for assessment and intervention.

Unnatural selection: reducing antibiotic resistance in neonatal units.

Antibiotic use selects for antibiotic resistant bacteria. This is an example of rapid Darwinian natural selection in action. It occurs in neonatal intensive care units with the use of parenteral antibiotics, and in the community with oral antibiotic use. A 10 point plan is put forward to reduce antibiotic resistance in neonatal units.

Early onset neonatal meningitis in Australia and New Zealand, 1992-2002.

OBJECTIVES: To study the epidemiology of early onset neonatal bacterial meningitis (EONBM) in Australasia. DESIGN: Prospective surveillance study, 1992-2002, in 20 neonatal units in Australia and New Zealand. EONBM was defined as meningitis occurring within 48 hours of delivery. RESULTS: There were 852 babies with early onset sepsis, of whom 78 (9.2%) had EONBM. The incidence of early onset group B streptococcal meningitis fell significantly from a peak of 0.24/1000 live births in 1993 to 0.03/1000 in 2002 (p trend = 0.002). There was no significant change over time in the incidence of Escherichia coli meningitis. The rate of EONBM in very low birthweight babies was 1.09/1000 compared with the rate in all infants of 0.11/1000. The overall rate of EONBM was 0.41/1000 in 1992 and 0.06 in 2001, but this trend was not significant (p trend = 0.07). Case-fatality rates for EONBM did not change significantly with time. Birth weight <1500 g (odds ratio (OR) 7.2 (95% confidence interval (CI) 4.8 to 10.9)) and Gram negative bacillary meningitis (OR 3.3 (95% CI 2.2 to 4.9)) were significant risk factors for mortality. Sixty two percent of the 129 babies who died from early onset sepsis or suspected sepsis did not have a lumbar puncture performed. CONCLUSION: The incidence of early onset group B streptococcal meningitis has fallen, probably because of maternal intrapartum antibiotic prophylaxis, without a corresponding change in E. coli meningitis. Gram negative bacillary meningitis still carries a worse prognosis than meningitis with a Gram positive organism.

Problems in determining the etiology of community-acquired childhood pneumonia.

Fifty-seven children ages 1 month to 12 years hospitalized because of community-acquired pneumonia were compared with age-matched controls who had acute asthma without pneumonia to test the value of rapid bacterial antigen detection and clinical and radiographic criteria for diagnosis of bacterial pneumonia. Bacterial pneumonia, defined on the basis of positive cultures of blood or pleural fluid, was diagnosed in 4 children (7%), 1 of whom also had viral pneumonia. Viral pneumonia, defined as a positive nasopharyngeal sample or positive serology, was diagnosed in 20 children (35%). Serum and concentrated urine were tested by latex agglutination (Wellcogen) for Haemophilus influenzae type b and pneumococcal antigens and by countercurrent immunoelectrophoresis for pneumococcal antigens. Pneumococcal antigen could not be detected in serum or urine from 3 children with culture-proved pneumococcal pneumonia, indicating poor sensitivity of the tests. In contrast apparent H. influenzae type b antigenuria was detected by latex agglutination in 4 of 40 children with pneumonia but also in 5 of 57 controls, and a sensitive enzyme-linked immunosorbent assay for polyribosyl ribitol (PRP) phosphate antigen showed that all 9 cases were false positives. The specificity of H. influenzae type b antigen detection was thus poor. Children with viral and bacterial pneumonia could not be distinguished by radiographic or clinical criteria (symptoms, fever) or by total or differential white blood cell counts, serum C-reactive protein or nasal or serum interferon levels. It is not possible to distinguish reliably childhood viral from bacterial pneumonia clinically or by rapid diagnostic tests.

Intrapartum antibiotics and early onset neonatal sepsis caused by group B Streptococcus and by other organisms in Australia. Australasian Study Group for Neonatal Infections.

OBJECTIVE: Early onset group B streptococcal (EOGBS) infection, the major neonatal infection in industrialized countries, can be prevented by intrapartum antibiotics, but population studies are lacking. This study aimed to determine the incidence of early onset infections caused by group B Streptococcus (GBS) and other organisms in Australia and to assess intrapartum antibiotic use. DESIGN: Longitudinal, prospective surveillance of neonatal infections in Australian neonatal units from 1991 to 1997. Early onset infection defined as clinical sepsis in first 48 h after birth, with positive cultures of blood or cerebrospinal fluid or positive urine GBS antigen detection. RESULTS: The incidence of EOGBS sepsis fell from 2.0 per 1000 live births (95% confidence interval, 1.4, 2.5) in 1991 to 1993, to 1.3 (1.2, 1.4) in 1993 to 1995, to 0.5 (0.4, 0.7) in 1995 to 1997 (P < 0.0001). The incidence in Aboriginal babies was 5.2 (1.8, 8.6) in 1991 to 1993, 5.1 (3.0, 7.2) in 1993 to 1995 and 1.8 (1.1, 2.5) in 1995 to 1997 (P < 0.05). The incidence of early onset infections caused by organisms other than GBS also fell, from 1.2 per 1000 live births (0.8, 1.7) in 1991 to 1993, to 0.8 (0.7, 0.9) in 1993 to 1995 and 0.5 (0.3, 0.7) in 1995 to 1997 (P < 0.0001). In 1991, 3 of 9 study hospitals had a formal policy on intrapartum antibiotic use, whereas in 1997 all 11 hospitals had a formal policy (P=0.002). CONCLUSIONS: A steady fall in EOGBS infections in Australia from 1991 to 1997 has been associated with increasing use of intrapartum antibiotics. Increased antibiotic use is probably causal in the fall in GBS, because the incidence of early onset infections caused by other organisms has also fallen.

Clinical and diagnostic features of osteomyelitis occurring in the first three months of life.

We report a retrospective study of 94 infants, ages < 4 months, who underwent investigation for possible osteomyelitis during a 9-year period. Of the 30 babies with proven osteomyelitis (radiographic changes or positive bone cultures or positive blood cultures plus a compatible clinical picture), 17 were preterm artificially ventilated babies and 4 were full term infants receiving intensive care. An etiologic organism was isolated from 28: methicillin-susceptible Staphylococcus aureus, 16; methicillin-resistant S. aureus (MRSA), 7; Escherichia coli, 3; and group B Streptococcus, 2. MRSA occurred exclusively in the preterm group. Osteomyelitis was multifocal in 40% and associated with septic arthritis in 47%. The long bones were frequently affected (80%) whereas the flat bones were often sites of clinically silent disease. Twenty-five (83.3%) of the 30 babies with proven osteomyelitis had focal clinical signs or evidence of disseminated staphylococcal disease. Only 10 were febrile. Four of 27 babies investigated because of positive blood cultures for S. aureus but no focal signs had osteomyelitis, as did only 1 of 27 babies with suspected sepsis but no focal signs. The sensitivity of 99mTc bone scanning was 84%, specificity 89%, positive predictive value 79% and negative predictive value 92%. The addition of gallium scanning (in 39 of the 94 infants) improved the respective figures to 90, 97, 93 and 95% and was useful in interpreting equivocal bone scans.

The efficacy of intranasal interferon alpha-2a in respiratory syncytial virus infection in volunteers.

In a double-blind, placebo-controlled study, self-administered intranasal interferon alpha-2a or placebo was given both before and after challenge with respiratory syncytial virus. The incidence of colds and the severity of signs and symptoms were reduced in those receiving interferon alpha-2a as compared with those given placebo. In a further double-blind, placebo-controlled study, self-administered interferon alpha-2a or placebo was given only to those volunteers who developed colds following challenge with respiratory syncytial virus. There was no evidence that interferon alpha-2a reduced the severity of the signs and symptoms or shortened the duration of the illness. The similarity of these results to the effect of interferon alpha-2a in rhinovirus infections in volunteers is discussed.

Racial differences in red cell indices.

A high prevalence of iron deficiency was found in apparently healthy Asian immigrant children in Harrow. After excluding children with overtly abnormal red cell indices, Asian and European children had identical haemoglobin values, but Asian children had much lower mean cell volume and mean corpuscular haemoglobin values and higher red blood cell values.

Serum immunoglobulin concentrations in preschool children measured by laser nephelometry: reference ranges for IgG, IgA, IgM.

Serum immunoglobulin concentrations were determined on sera from 298 healthy children aged six months to six years using the Hyland laser nephelometer PDQ system. Age-specific 95% reference ranges for serum IgG, IgA and IgM are presented; considerable care has been taken to ensure statistical validity of the reference ranges. The wide range of values in children under two years suggest that measuring immunoglobulin concentrations in this age group is of little value in diagnosing immunodeficiency.

Cryptosporidiosis in immunocompetent children.

Cryptosporidial oocysts were identified by modified Ziehl-Neelsen stain in the stools of seven (3.2%) of 213 children with acute or chronic diarrhoea and one (0.9%) of 112 controls. All children with cryptosporidia were immunocompetent. Four of the index cases had a short illness (3-14 days) with watery diarrhoea, vomiting (2), and abdominal pain (2). Two index cases had chronic diarrhoea for over four months and failure to thrive. Both had a small intestinal enteropathy; one had cryptosporidial oocysts in stool specimens two months apart and the other had cryptosporidial schizonts attached to the jejunal mucosa. One index case had a colitis of indeterminate cause. Four of the index cases had recently travelled abroad. There had been an outbreak of gastroenteritis in the family of one of the index cases, and three affected sisters and an asymptomatic brother had oocysts in their stools. Cryptosporidial infestation seems to be associated with acute gastroenteritis and sometimes with chronic diarrhoea and small bowel damage in immunocompetent children.

Carbohydrate-protein conjugate vaccines.

Various pathogenic bacteria have coats of polysaccharide, many with repeating epitopes. Though polysaccharide vaccines have been available for some time, they induce mainly IgM production, and are only moderately protective in adults and ineffective in young children. It was originally shown in 1931 that the immunogenicity of polysaccharides could be enhanced by conjugating to a protein. The last two decades have witnessed the production and clinical testing of polysaccharide-protein conjugates specific for at least four different bacteria which normally cause considerable mortality and morbidity, especially in young children. In some cases, immunizing children from 4 months of age, with a booster early in the second year, has resulted in remarkably high success rates in protecting them from disease. For one pathogen, Haemophilus influenza type b, the success rate has been sufficiently high (> 95%) to suggest that this disease might, in time, be globally controlled in this way. The results of immunization with conjugate vaccines to Streptococcus pneumoniae, Neisseria meningiditis and Salmonella typhi are also very encouraging. More conjugate preparations are under development.

Ethnicity and seizure threshold.

1. Seizure threshold is an important variable in modern ECT treatment planning. To date, age, gender, and electrode placement have been used to predict seizure threshold, but the potential impact of ethnicity has received little attention. 2. In a retrospective pilot study of patients who received ECT, 20 pairs of first admission, right unilateral-treated, age- and sex-matched black and white patients were compared. 3. Black patients had higher seizure thresholds and were more likely to require restimulation, despite the finding that they were more likely to have been receiving concomitant medications which lower seizure threshold. However, ethnicity was confounded with variations in ECT dose titration, which were the strongest predictor of seizure threshold. 4. There were no differences in seizure length. Further study is necessary to confirm the impact of ethnicity on seizure threshold.

Surveillance of colonization and late-onset septicaemia in neonates.

Twenty-seven newborns had an episode of late-onset sepsis (septicaemia or bacterial meningitis after 48 h of age) over an 18 month period. Preceding or simultaneous surface cultures were available from 26 babies. Colonization with the organism causing sepsis could only be documented in 10 cases. Colonization with aminoglycoside-resistant Gram negative organisms was common but there were only two cases of systemic sepsis with a resistant organism. Pseudomonas aeruginosa frequently colonized babies over the first 8 months of the survey, but subsequently virtually ceased to colonize babies, although it continued to be a common cause of late-onset sepsis. These findings do not support the utility of routine surveillance of organisms colonizing neonates in predicting bacteria causing late-onset sepsis. They also cast doubt on the value of eliminating colonizing organisms by expensive infection control measures.

Repeated prevalence surveys of paediatric hospital-acquired infection.

Hospital-acquired infection (HAI) results in an enormous burden of excess morbidity, mortality and cost in both adults and children. Monitoring HAI is difficult, especially with limited resources, but it is vital if infection control measures are to be appropriately implemented and assessed. Cross-sectional prevalence surveys, repeated every six months, have been used effectively to monitor HAI in adults, but this technique has not been previously employed in the paediatric population. We performed prevalence surveys of HAI on a single day once every six months for five years, using a standardized questionnaire. Of the 1623 inpatients surveyed, 125 (7.7%) had HAI and 352 (21%) had community-acquired infection. In those with HAI, central-line infections, pneumonia, and wound infections predominated. A hospital stay of greater than seven days was associated with a sixfold increase in the risk of HAI. In addition, admission to a paediatric or neonatal intensive care unit, the presence of a urinary or vascular catheter, the presence of an endotracheal tube, immunosuppression and recent surgery were all associated with a significantly increased risk of HAI. In contrast to other studies, younger children were not at increased risk of HAI; admission to the neonatal unit, rather than age per se, was associated with increased risk. We conclude that repeated prevalence surveys enable simple and cost-effective assessment of HAI, facilitating appropriate infection control interventions. They should be used more widely in the paediatric setting.

The reliability of serological tests for the diagnosis of genital herpes: a critique.

The reliability and limitations of the currently used routine tests for herpes simplex virus type 2 (HSV-2) antibody in Australia are reviewed. Six case reports illustrate the clinical dangers of overinterpretation of the currently available kits and the need for a readily available specific HSV-2 antibody test. In Sydney, HSV-2 causes approximately 85% of primary genital herpes and > 95% of recurrent genital herpes. Due to the extensive serological cross-reactivity between HSV-1 and HSV-2, currently available "type specific" commercial assays cannot reliably distinguish between the 2. Isolation of herpes simplex virus (HSV) or detection of HSV antigen in vesicle fluid is the preferred diagnostic test but may be overlooked or patients may have no visible lesions. The only accurate techniques for detecting HSV-2 specific antibody are the Western blot assay and an enzymatic immunoassay using glycoprotein G (gG-2), a component of the HSV-2 envelope. These tests, which still are restricted to research laboratories can be used to accurately identify people with previous exposure to HSV-2 (IgG) or to diagnose primary infection where virus isolation has not been performed or is impossible. Current commercially available antibody tests may have extensive cross-reactivity.

A ten year, multicentre study of coagulase negative staphylococcal infections in Australasian neonatal units.

OBJECTIVE: To study late onset systemic infections with coagulase negative staphylococci. METHODS: Prospective longitudinal study of coagulase negative staphylococcal infection in 18 Australasian neonatal nurseries. RESULTS: From 1991 to 2000 inclusive, there were 1281 cases of coagulase negative staphylococcal (CoNS) sepsis, comprising 57.1% of all late onset infections. The male/female ratio was 1.27:1 (p < 0.05). The incidence of CoNS sepsis was 3.46 episodes per 1000 live births. Most infected babies (71%) were 24-29 weeks gestation at birth (mode 26 weeks). The first positive culture was day 7-14 in 49% of babies (mode 10 days). Five cases of meningitis were reported, an incidence of 0.4% of all CoNS infections. Twenty nine babies (2.3%) had concurrent necrotising enterocolitis and CoNS septicaemia. Four babies (0.3%) died from CoNS infection, but CoNS infection possibly contributed to the death of an additional 20 babies (1.6%). The mortality directly attributable to CoNS infection was significantly lower than that from late onset infections with Staphylococcus aureus (13.1%; relative risk (RR) = 36.1 (95% confidence interval (CI) 13.0 to 100.2) or with Gram negative bacilli (14.2%; RR = 45.5 (95% CI 16.8 to 123.3)). CONCLUSIONS: CoNS are currently responsible for most late onset neonatal infections. Most infected babies are < 30 weeks gestation at birth, and usually present between 7 and 14 days of age. CoNS infections may be associated with necrotising enterocolitis, although causality is unproven. Neonatal CoNS infections are relatively benign: meningitis is rare and mortality low compared with infection from other organisms. Over-vigorous attempts to reduce the incidence of CoNS infections using prophylactic antibiotics are not advisable.

Staphylococcus aureus infections in Australasian neonatal nurseries.

OBJECTIVE: To study the incidence and outcome of systemic infections with methicillin sensitive (MSSA) and methicillin resistant Staphylococcus aureus (MRSA) infections in Australasian neonatal nurseries. METHODS: Prospective longitudinal study of systemic infections (clinical sepsis plus positive cultures of blood and/or cerebrospinal fluid) in 17 Australasian neonatal nurseries. RESULTS: The incidence of early onset sepsis with S aureus, mainly MSSA, was 19 cases per 244 718 live births or 0.08 per 1000. From 1992 to 1994, MRSA infections caused only 8% of staphylococcal infections. From 1995 to 1998, there was an outbreak of MRSA infection, in two Melbourne hospitals. The outbreak resolved, after the use of topical mupirocin and improved handwashing. Babies with MRSA sepsis were significantly smaller than babies with MSSA sepsis (mean birth weight 1093 v 1617 g) and more preterm (mean gestation 27.5 v 30.3 weeks). The mortality of MRSA sepsis was 24.6% compared with 9.9% for MSSA infections. The mortality of early onset MSSA sepsis, however, was 39% (seven of 18) compared with 7.3% of late onset MSSA infection presenting more than two days after birth. CONCLUSIONS: S aureus is a rare but important cause of early onset sepsis. Late onset MRSA infections carried a higher mortality than late onset MSSA infections, but babies with early onset MSSA sepsis had a particularly high mortality.