Rosalinde Hurley

Bacteriology of abscesses of the central nervous system: a multicentre prospective study.

Pus from 46 patients with abscesses of the central nervous system (CNS) was examined for bacteria; bacteria were found in all patients. Streptococci were isolated from 36 patients and most isolates were Streptococcus milleri, Lancefield Group F, Ottens and Winkler type O III. Staphylococci were isolated from nine patients, organisms of the bacteroides group from 11, Proteus spp from seven, Klebsiella aerogenes from one, and Haemophilus aphrophilus from one. Pure cultures predominated over mixed cultures. Streptococci were isolated from abscesses of all types, and at all sites, but members of the Enterobacteriaceae and of the bacteroides group were isolated, in mixed cultures, principally from abscesses of the temporal lobe secondary to infection of the middle ear. Staphylococci predominated in abscesses that followed accidental or surgical trauma. Compared with fully sensitive control organisms, microbes infecting half the patients were resistant to penicillin. The prognosis of abscess of the CNS is grave, and the microbiological findings have important consequences for treatment. Prompt inoculation of specimens to culture plates and prompt incubation are mandatory if bacteria are to be cultured. Inhibitors of antimicrobial agents should be added to culture media if antibiotics have been administered. Provided that the site of the abscess and the antecedent history are ascertainable, the neurosurgeon should be able to start appropriate treatment while awaiting the results of culture.

Infantile meningitis in England and Wales: a two year study.

A two year prospective study identified 1922 cases of meningitis in children under 1 year of age. A further 201 cases were identified from other sources. The annual incidence of meningitis during the first year of life was 1.6/1000; during the first 28 days of life it was 0.32/1000, and among postneonatal infants it was 1.22/1000. The male:female ratio was 1.4:1. The overall case fatality rate was 19.8% for neonates and 5.4% for postneonatal infants. Two thirds of deaths identified in the study, 50% of all deaths, were not attributed to meningitis by the Office of Population Censuses and Surveys. Group B beta haemolytic streptococci (28%), Escherichia coli (18%), and Listeria monocytogenes (5%) were most frequently isolated from neonates and Neisseria meningitidis (31%), Haemophilus influenzae (30%), and Streptococcus pneumoniae (10%) from postneonatal infants. At 2-6 months of age N meningitidis meningitis was most common, and at 7-12 months H influenzae predominated. Meningitis caused by group B beta haemolytic streptococci occurred up to 6 months of age and had a consistent mortality of 25%. Neonatal meningitis due to Gram negative enteric rods had a mortality of 32%. Low birth weight was a significant predisposing factor for both neonates and postneonatal infants. In both groups mortality was significantly higher among children admitted in coma. There was no seasonal variation in incidence in either group. Neonates were treated with either group. Neonates were treated with either chloramphenicol (50%) or gentamicin (48%) usually in combination with a penicillin; 40% received a third generation cephalosporin. Of the 1472 postneonatal infants treated 84% received chloramphenicol with a penicillin and 10% received a third generation cephalosporin. Relapse occurred in 49 patients and three died. Eighteen babies coned as a result of raised intracranial pressure, including four neonates, and four died. Mortality among the 133 (7%) children who received steroids was significantly higher than in the rest of the study group.

FREQUENCY OF MYCOPLASMA IN FERTILE AND INFERTILE COUPLES

Abstract 120 infertile couples and 92 pregnant women and 38 of their consorts were studied to ascertain the frequency of mycoplasmas in the genital tract. Mycoplasma hominis was isolated from one or both partners in 13.2% of 38 fertile couples and 14.7% of 109 infertile couples; T mycoplasmas were isolated from one or both partners in 52.6% of fertile couples and 57.2% of infertile couples. The differences are not statistically significant, and do not support the suggestion that mycoplasmas are associated with failure to conceive. A double-blind controlled trial of doxycycline in infertile patients showed that the drug eradicates mycoplasmas from the genital tract, and that a single dose of 100 mg. ensures an inhibitory level in szerum and seminal fluid for twenty-four hours. The treatment was given for twenty-eight days, and its effect, if any, on primary infertility has yet to be determined.

Chloramphenicol toxicity in neonates: its incidence and prevention.

The incidence of dose related chloramphenicol toxicity was determined in 64 neonates from 12 hospitals. Ten of the 64 exhibited symptoms attributed clinically to chloramphenicol toxicity. Nine received the dose prescribed and one an overdose. Symptoms of the grey baby syndrome were observed in five of the 10 babies; four babies suffered reversible haematological reactions; and one baby was described as very grey. Peak serum chloramphenicol concentrations in these 10 babies ranged from 28 to 180 mg/l and trough concentrations from 19 to 47 mg/l. Serum chloramphenicol concentrations above the therapeutic range (15-25 mg/l) were observed in a further 27 neonates (two had received a 10-fold overdose), none of whom showed signs of toxicity. Serious toxicity was associated with either prescription of dosages greater than that recommended or overdosage of chloramphenicol. High concentrations in young neonates may be avoided by prescribing and giving the recommended dose and then careful monitoring; concentrations should be maintained between 15 and 25 mg/l. No babies with concentrations within this range showed clinical signs of toxicity.

Antibiotic treatment of abscesses of the central nervous system.

Samples of intracranial pus and serum from 32 patients were assayed to determine the concentrations reached in them of penicillin, ampicillin, cloxacillin, cephaloridine, gentamicin, chloramphenicol, fusidic acid, and lincomycin. Metronidazole had not been given. Penicillin penetrated abscesses reasonably well, but other beta-lactam antibiotics did not. The penetration of chloramphenicol was erratic. Aminoglycosides penetrated poorly, but lincomycin and fusidic acid penetrated well. Assay of sulphonamides and co-trimoxazole in pus was unreliable. These studies indicate that treatment of abscesses of the central nervous system should be considered according to the site and the likely antecedent cause. Abscesses of sinusitic origin, usually in the frontal lobe, yield penicillin-sensitive streptococci. Penicillin is the drug of choice. Abscesses of otitic origin, usually in the temporal lobe, yield a mixed flora, often including anaerobic bacteria. Multiple antibiotic therapy is indicated. Abscesses of metastatic or cryptogenic origin yield streptococci or mixed cultures, and multiple therapy is appropriate while awaiting the bacteriological results. Spinal and post-traumatic abscesses yield Staphylococcus aureus, and fusidic acid is the drug of choice.

Inactivation of penicillin by purulent exudates.

Four of 22 specimens of human pus inactivated up to 90% of added penicillin within one hour in vitro. Ampicillin and cephaloridine were also inactivated, but streptomycin and fusidic acid were not. The effect was not related to the protein content of the pus, nor to its pH value. Microbes that may produce beta-lactamase in small quantities were isolated from three of the four specimens, but the enzyme was not detected in the pus by physical methods nor by microbiological inhibition assay. The inactivating effect was shown to be a property of the solid portion of the pus, and was absent from the filtrate. We suggest that the effect may be an intrinsic property of the host, which should be investigated further as it has important implications for clinical practice.

Microbial flora of the lower genital tract during pregnancy: relationship to morbidity.

Nineteen genera and groups of micro-organisms were isolated from the lower genital tract of 280 women at their first antenatal visit. Chlamydia, viruses, and T-strain mycoplasmas were not sought, and only routine methods of anaerobic culture were used. Growth was recorded as scanty, moderate or heavy. The population studied was grouped according to age, parity, gestational stage at booking, presence and degree of severity of lower genital tract morbidity, past history of vulvovaginitis, and suspicion of lower genital tract morbidity as evidenced by a request for a report on the microbiological findings. The frequency of isolation of the various microbes in health and in disease is given. The grading of Gram-stained smears bore no relation to the isolation rates of lactobacilli, but there was a significant increase (p less than 0-001) in the isolation rates of each of the following: Mycoplasma hominis, Bacteroides spp., Trichomonas vaginalis, Gram-variable cocco-bacilli, and anaerobic streptococci in those patients with smears in which lactobacilli were adjudged to be absent. The isolation of faecal streptococci was increased (p less than 0-001) in women aged more than 34 years. Escherichia coli (p less than 0-05) and anaerobic and microaerophilic streptococci (p less than 0-02) were isolated more frequently from those booking after the 25th week of pregnancy. The incidence of M. hominis (p less than 0-02) and of anaerobic streptococci (p less than 0-05) increased between the first and third trimesters. No significance positive correlations were established between the isolation rates of the various microbes and objective assessment of lower genital tract morbidity or the demonstration of pus cells, but lactobacilli were isolated less frequently (p less than 0-01) from those with morbidity. The isolation of Candida albicans (p less than 0-02), T. vaginalis (p less than 0-05), and M. hominis (p less than 0.05) was increased in patients in whom vulvovaginitis was suspected, and that of T. vaginalis (p less than 0-05) was increased in those with a past history of vulvovaginitis. The study indicates that, other than the pathogens T. vaginalis and C. albicans, only M. Hominis could be suspected, on statistical grounds, of being associated with disease of the lower genital tract during early pregnancy.

Incidence of potentially toxic concentrations of gentamicin in the neonate.

The incidence of putatively toxic serum concentrations and the factors influencing their occurrence were investigated in a study of 91 neonates receiving parenteral gentamicin twice daily at a dose of mean (SD) 5.5 (0.1) mg/kg/day. Most neonates were preterm and of low birthweight. Serum concentrations, area under the curve (AUC), and clearance were calculated. Potentially toxic trough concentrations (greater than 2 mg/l) were recorded in 57 of 91 (63%) neonates; 24 of these had trough concentrations greater than 3 mg/l. These babies were of a significantly lower gestational age and were younger than the remainder of the population. Toxic trough concentrations were not accompanied by raised peak serum values. A wide variation in all pharmacokinetic variables was observed. Peak serum concentration was most highly correlated with dose, while trough concentration, AUC, and clearance were more dependent on postnatal age. Clearance of gentamicin decreased significantly with increasing serum urea and creatinine concentrations. Preterm neonates in the first week of life are likely to develop potentially toxic serum concentrations when receiving the currently recommended dose of gentamicin (5-6 mg/kg/day). To prevent accumulation the dosage interval may need to be increased to 18 hours in these babies.

Genital mycoplasmas and birth weight in offspring of primigravid women

The relationship between colonization of pregnant women by Ureaplasma and Mycoplasma and the outcome of pregnancy in a study of 104 women is reported. There were eight abortions but no multiple births or stillbirths. Excluding abortions, the mean gestational length was 39.6 weeks and the corrected mean birth weight was 3.28 kilograms. There was no relationship between maternal colonization by genital mycoplasmas and reduction in birth weight of the offspring, but five of the eight women who aborted harbored Ureaplasma, suggesting an increased trend toward abortion in women harboring Ureaplasma.

A search for triple X females in a fertile population.

Buccal smears of 3536 puerperal women have been examined and one example of 47 XXX karyotype found in this fertile population. One other triple X female was found during the pilot survey of 100 women. Four males with the karyotype 47 XXY were found among 1811 newborn males. No sex chromosome abnormality was detected in 1678 newborn females.