Impact of obstetric interventions on condition at birth in extremely preterm babies: evidence from a national cohort study

Background

To investigate perinatal decision-making and the use of obstetric interventions, we examined the effects of antenatal steroids, tocolysis, and delivery mode on birth in a good condition (defined as presence of an infant heart rate >100 at five minutes of age) and delivery-room (DR) death in extremely preterm deliveries.

Methods

Prospective cohort of all singleton births in England in 2006 at 22–26 weeks of gestation where the fetus was alive at the start of labour monitoring or decision to perform caesarean section. Odds ratios adjusted for potential confounders (aOR) were calculated using logistic regression.

Results

One thousand seven hundred twenty two singleton pregnancies were included. 1231 women received antenatal steroids, 437 tocolysis and 356 delivered by Caesarean section. In babies born vaginally, aOR between a partial course of steroids and improved condition at birth was 1.84, 95% CI: 1.20 to 2.82 and, for a complete course, 1.63, 95% CI: 1.08 to 2.47; for DR death, aORs were 0.34 (0.21 to 0.55) and 0.41 (0.26 to 0.64) for partial and complete courses of steroids. No association was seen for steroid use in babies delivered by Caesarean section. Tocolysis was associated with improved condition at birth (aOR 1.45, 95% CI: 1.05 to 2.0) and lower odds of death (aOR 0.48, 95% CI: 0.32 to 0.73). In women without spontaneous labour, Caesarean delivery at ≤24 and 25 weeks was associated with improved condition at birth ((aORs 12.67 (2.79 to 57.60) and 4.94 (1.44 to 16.90), respectively) and lower odds of DR death (aORs 0.03 (0.01 to 0.21) and 0.13 (0.03 to 0.55)). There were no differences at 26 weeks gestation or in women with spontaneous labour.

Conclusions

Antenatal steroids are strongly associated with improved outcomes in babies born vaginally. Tocolysis was associated with improvements in all analyses. Effects persisted after adjustment for perinatal decision-making. However, associations between delivery mode and birth outcomes may be attributable to case selection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-1154-y) contains supplementary material, which is available to authorized users.

Perinatal outcomes for extremely preterm babies in relation to place of birth in England: the EPICure 2 study

BACKGROUND

Expertise and resources may be important determinants of outcome for extremely preterm babies. We evaluated the effect of place of birth and perinatal transfer on survival and neonatal morbidity within a prospective cohort of births between 22 and 26 weeks of gestation in England during 2006.

METHODS

We studied the whole population of 2460 births where the fetus was alive at the admission of the mother to hospital for delivery. Outcomes to discharge were compared between level 3 (most intensive) and level 2 maternity services, with and without transfers, and by activity level of level 3 neonatal unit; ORs were adjusted for gestation at birth and birthweight for gestation (adjusted ORs (aOR)).

FINDINGS

Of this national birth cohort, 56% were born in maternity services with level 3 and 34% with level 2 neonatal units; 10% were born in a setting without ongoing intensive care facilities (level 1). When compared with level 2 settings, risk of death in level 3 services was reduced (aOR 0.73 (95% CI 0.59 to 0.90)), but the proportion surviving without neonatal morbidity was similar (aOR 1.27 (0.93 to 1.74)). Analysis by intended hospital of birth confirmed reduced mortality in level 3 services. Following antenatal transfer into a level 3 setting, there were fewer intrapartum or labour ward deaths, and overall mortality was higher for those remaining in level 2 services (aOR 1.44 (1.09 to 1.90)). Among level 3 services, those with higher activity had fewer deaths overall (aOR 0.68 (0.52 to 0.89)).

INTERPRETATION

Despite national policy, only 56% of births between 22 and 26 weeks of gestation occurred in maternity services with a level 3 neonatal facility. Survival was significantly enhanced following birth in level 3 services, particularly those with high activity; this was not at the cost of increased neonatal morbidity.

Diversity and stability of cultured vaginal lactobacilli in pregnant women from a multi-ethnic urban UK population

AIM

To determine the diversity and stability of cultured vaginal lactobacilli in a multi-ethnic population of pregnant women.

METHODS AND RESULTS

A single-centre, prospective, cohort study was performed in a tertiary perinatal centre in East London, UK. Self-collected vaginal swabs at 13 and 20 weeks gestation were obtained from women attending for routine antenatal care and cultured for lactobacilli. In women who provided both swabs, 37 of 203 (18%) had no lactobacilli cultured at either time. Only 53 (26%) had the same species at both times. Black women were less likely to have lactobacilli cultured at 13 weeks (P = 0·014), and Black and Asian women were less likely to have lactobacilli cultured at 20 weeks (P = 0·002) compared with those in the White and Other groups.

CONCLUSIONS

Significant differences exist between ethnic groups in the carriage and stability of vaginal lactobacilli.

SIGNIFICANCE AND IMPACT OF THE STUDY

These differences have implications for the design of interventions aimed at normalizing the vaginal microbiota in pregnant women.

Neurological and developmental outcome in extremely preterm children born in England in 1995 and 2006: the EPICure studies

OBJECTIVE

To determine outcomes at age 3 years in babies born before 27 completed weeks' gestation in 2006, and to evaluate changes in outcome since 1995 for babies born between 22 and 25 weeks' gestation.

DESIGN

Prospective national cohort studies, EPICure and EPICure 2.

SETTING

Hospital and home based evaluations, England.

PARTICIPANTS

1031 surviving babies born in 2006 before 27 completed weeks' gestation. Outcomes for 584 babies born at 22-25 weeks' gestation were compared with those of 260 surviving babies of the same gestational age born in 1995.

MAIN OUTCOME MEASURES

Survival to age 3 years, impairment (2008 consensus definitions), and developmental scores. Multiple imputation was used to account for the high proportion of missing data in the 2006 cohort.

RESULTS

Of the 576 babies evaluated after birth in 2006, 13.4% (n=77) were categorised as having severe impairment and 11.8% (n=68) moderate impairment. The prevalence of neurodevelopmental impairment was significantly associated with length of gestation, with greater impairment as gestational age decreased: 45% at 22-23 weeks, 30% at 24 weeks, 25% at 25 weeks, and 20% at 26 weeks (P<0.001). Cerebral palsy was present in 83 (14%) survivors. Mean developmental quotients were lower than those of the general population (normal values 100 (SD 15)) and showed a direct relation with gestational age: 80 (SD 21) at 22-23 weeks, 87 (19) at 24 weeks, 88 (19) at 25 weeks, and 91 (18) at 26 weeks. These results did not differ significantly after imputation. Comparing imputed outcomes between the 2006 and 1995 cohorts, the proportion of survivors born between 22 and 25 weeks' gestation with severe disability, using 1995 definitions, was 18% (95% confidence interval 14% to 24%) in 1995 and 19% (14% to 23%) in 2006. Fewer survivors had shunted hydrocephalus or seizures. Survival of babies admitted for neonatal care increased from 39% (35% to 43%) in 1995 to 52% (49% to 55%) in 2006, an increase of 13% (8% to 18%), and survival without disability increased from 23% (20% to 26%) in 1995 to 34% (31% to 37%) in 2006, an increase of 11% (6% to 16%).

CONCLUSION

Survival and impairment in early childhood are both closely related to gestational age for babies born at less than 27 weeks' gestation. Using multiple imputation to account for the high proportion of missing values, a higher proportion of babies admitted for neonatal care now survive without disability, particularly those born at gestational ages 24 and 25 weeks.

Short term outcomes after extreme preterm birth in England: comparison of two birth cohorts in 1995 and 2006 (the EPICure studies)

OBJECTIVE

To determine survival and neonatal morbidity for babies born between 22 and 26 weeks' gestation in England during 2006, and to evaluate changes in outcome since 1995 for babies born between 22 and 25 weeks' gestation.

DESIGN

Prospective national cohort studies.

SETTING

Maternity and neonatal units in England.

PARTICIPANTS

3133 births between 22 and 26 weeks' gestation in 2006; 666 admissions to neonatal units in 1995 and 1115 in 2006 of babies born between 22 and 25 weeks' gestation.

MAIN OUTCOME MEASURES

Survival to discharge from hospital, pregnancy and delivery outcomes, infant morbidity until discharge.

RESULTS

In 2006, survival of live born babies was 2% (n=3) for those born at 22 weeks' gestation, 19% (n=66) at 23 weeks, 40% (n=178) at 24 weeks, 66% (n=346) at 25 weeks, and 77% (n=448) at 26 weeks (P<0.001). At discharge from hospital, 68% (n=705) of survivors had bronchopulmonary dysplasia (receiving supplemental oxygen at 36 weeks postmenstrual age), 13% (n=135) had evidence of serious abnormality on cerebral ultrasonography, and 16% (n=166) had laser treatment for retinopathy of prematurity. For babies born between 22 and 25 weeks' gestation from March to December, the number of admissions for neonatal care increased by 44%, from 666 in 1995 to 959 in 2006. By 2006 adherence to evidence based practice associated with improved outcome had significantly increased. Survival increased from 40% to 53% (P<0.001) overall and at each week of gestation: by 9.5% (confidence interval -0.1% to 19%) at 23 weeks, 12% (4% to 20%) at 24 weeks, and 16% (9% to 23%) at 25 weeks. The proportions of babies surviving in 2006 with bronchopulmonary dysplasia, major cerebral scan abnormality, or weight and/or head circumference <-2 SD were similar to those in 1995, but the proportion treated for retinopathy of prematurity had increased from 13% to 22% (P=0.006). Predictors of mortality and morbidity were similar in both cohorts.

CONCLUSION

Survival of babies born between 22 and 25 weeks' gestation has increased since 1995 but the pattern of major neonatal morbidity and the proportion of survivors affected are unchanged. These observations reflect an important increase in the number of preterm survivors at risk of later health problems.

Respiratory health in pre-school and school age children following extremely preterm birth

RATIONALE

Increasing survival at extremely low gestational ages is associated with very high rates of bronchopulmonary dysplasia (BPD) but is rarely quantified.

OBJECTIVES

To identify respiratory morbidity and risk factors in the EPICure cohort over the first 6 years of life.

METHODS

308 babies born at < or =25 weeks' gestation in 1995 were followed up at 30 months and 6 years of age. Respiratory outcome was evaluated using clinical assessment, parental questionnaire and peak expiratory flow (PEF) at 6 years.

RESULTS

74% of this population received supplemental oxygen at 36 weeks postmenstrual age and 36% were discharged with supplemental oxygen which continued for a median of 2.5 months (75th percentile: 8.5 months). 236 children were followed to 6 years. Respiratory symptoms and medication use were more prevalent at 30 months and 6 years in children with BPD compared to those without. Children without BPD (n = 56) were not significantly different from their classmates but had consistently higher prevalence of poor respiratory health. Symptoms, need for hospital admission and medication use declined between 30 months and 6 years. 200 index children completed three PEF measures; PEF was lower than in classmates (mean adjusted difference: 39 l/min (95% CI 30 to 47)) and was lowest in children discharged home with oxygen and in those with BPD. Gestational age, BPD and maternal smoking at home and in pregnancy were independent risk factors for symptoms, but BPD was the only independent associate of PEF.

CONCLUSION

Extremely preterm children have a continuum of poor respiratory health over the first 6 years, which is exacerbated by smoking during pregnancy and in the home.

The EPICure study: growth and blood pressure at 6 years of age following extremely preterm birth

BACKGROUND

Preterm children are at risk for reduced growth in early childhood, which may predispose them to later changes in blood pressure (BP).

OBJECTIVE

To study growth and BP in extremely preterm (EP) children at age 6 years.

METHODS

Children who were born at 25 completed weeks of gestation or less in the United Kingdom and Ireland in 1995 were evaluated when they reached early school age. Children underwent standardised assessments, including auxology and sitting BP.

RESULTS

Of 308 surviving children, 241 (78%) were assessed at a median age of 6 years 4 months; 160 full-term classmates acted as a comparison group. Compared with classmates, EP children were 1.2 standard deviations (SDs) lighter, 0.97 SD shorter, body mass index (BMI) was 0.95 SD lower and head circumference 1.3 SD lower. Compared with 2.5 years of age, EP children had shown "catch-up" in their weight by 0.37 SD, height by 0.42 SD and head circumference by 0.13 SD. Systolic and diastolic BP were lower by 2.3 mm Hg and 2.4 mm Hg, respectively, in EP children, but these differences were accounted for by differences in height and BMI. Maternal smoking in pregnancy was associated with lower BP. Children born before 24 weeks had higher systolic pressures and children given postnatal steroids higher diastolic pressures.

CONCLUSIONS

Poor postnatal growth seen after birth and in the third year persists into school age. Catch-up growth reduces some of the early deficit but is least for head growth. Despite serious postnatal growth restriction BP appears similar in both EP and term classmates.

Molecular diagnosis of vascular access device-associated infection in children being treated for cancer or leukaemia

Blood samples were collected for quantitative 16S rDNA analysis from the vascular access device (VAD) of patients presenting with fever at participating centres of the UK Children's Cancer and Leukaemia Group. In total, 260 of 301 episodes of fever were evaluable and were classified as probable, possible, unlikely or unclassifiable VAD-associated infection. The sensitivity of the 16S rDNA assay declined concomitantly with delays from time of presentation to sampling. The sensitivity with >0.125 pg of bacterial DNA/microL of whole blood was 80% for the 20 probable VAD-associated infections diagnosed with samples collected on the day of or day following presentation. The specificity rose with increasing amounts of bacterial DNA, from 93% with >0.125 pg, to 98% with 0.25-0.5 pg, and to 100% with >0.5 pg/microL blood. The positive predictive value (for probable or possible) was 88% (95% CI 70-98%) with 0.25 pg/microL, and 100% (95% CI 83-100%) with >0.5 pg/microL. All 18 (6.8%) episodes with >0.5 pg of bacterial DNA/microL blood were associated with positive blood cultures. Identifications derived from the DNA sequence were consistent with the blood culture identifications for 15 of the 17 episodes with a DNA sequence identification. The VAD was removed because of suspected infection in six (2.8%) of 216 episodes with <0.125 pg of bacterial DNA/microL, in one (5%) of 20 episodes with 0.125-0.25 pg/microL, in one (16.7%) of six episodes with 0.25-0.5 pg/microL, and in nine (50%) of 18 episodes with >0.5 pg/microL. A bacterial DNA concentration of >0.5 pg/microL in blood drawn through a central venous catheter at the time of fever presentation had a high positive predictive value for VAD-associated infection and predicted an increased risk of VAD removal because of suspected infection.

Motor and executive function at 6 years of age after extremely preterm birth

BACKGROUND

Studies of very preterm infants have demonstrated impairments in multiple neurocognitive domains. We hypothesized that neuromotor and executive-function deficits may independently contribute to school failure.

METHODS

We studied children who were born at < or = 25 completed weeks' gestation in the United Kingdom and Ireland in 1995 at early school age. Children underwent standardized cognitive and neuromotor assessments, including the Kaufman Assessment Battery for Children and NEPSY, and a teacher-based assessment of academic achievement.

RESULTS

Of 308 surviving children, 241 (78%) were assessed at a median age of 6 years 4 months. Compared with 160 term classmates, 180 extremely preterm children without cerebral palsy and attending mainstream school performed less well on 3 simple motor tasks: posting coins, heel walking, and 1-leg standing. They more frequently had non-right-hand preferences (28% vs 10%) and more associated/overflow movements during motor tasks. Standardized scores for visuospatial and sensorimotor function performance differed from classmates by 1.6 and 1.1 SDs of the classmates' scores, respectively. These differences attenuated but remained significant after controlling for overall cognitive scores. Cognitive, visuospatial scores, and motor scores explained 54% of the variance in teachers' ratings of performance in the whole set; in the extremely preterm group, additional variance was explained by attention-executive tasks and gender.

CONCLUSIONS

Impairment of motor, visuospatial, and sensorimotor function, including planning, self-regulation, inhibition, and motor persistence, contributes excess morbidity over cognitive impairment in extremely preterm children and contributes independently to poor classroom performance at 6 years of age.

TOIB Study. Are topical or oral ibuprofen equally effective for the treatment of chronic knee pain presenting in primary care: a randomised controlled trial with patient preference study. [ISRCTN79353052]

BACKGROUND

Many older people have chronic knee pain. Both topical and oral non- steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat this. Oral NSAIDS are effective, at least in the short term, but can have severe adverse effects. Topical NSAIDs also appear to be effective, at least in the short term. One might expect topical NSAIDs both to be less effective and to have fewer adverse effects than oral NSAIDs. If topical NSAIDs have fewer adverse effects this may outweigh both the reduction in effectiveness and the higher cost of topical compared to oral treatment. Patient preferences may influence the comparative effectiveness of drugs delivered via different routes.

METHODS

TOIB is a randomised trial comparing topical and oral ibuprofen, with a parallel patient preference study. We are recruiting people aged 50 or over with chronic knee pain, from 27 MRC General Practice Research Framework practices across the UK. We are seeking to recruit 283 participants to the RCT and 379 to the PPS. Participants will be followed up for up to two years (with the majority reaching one year). Outcomes will be assessed by postal questionnaire, nurse examination, laboratory tests and medical record searches at one and two years or the end of the study.

DISCUSSION

This study will provide new evidence on the overall costs and benefits of treating chronic knee pain with either oral or topical ibuprofen. The use of a patient preference design is unusual, but will allow us to explore how preference influences response to a medication. In addition, it will provide more information on adverse events. This study will provide evidence to inform primary care practitioners, and possibly influence practice.

The EPICure study: associations and antecedents of neurological and developmental disability at 30 months of age following extremely preterm birth

AIMS

To describe perinatal factors associated with later morbidity among extremely preterm children at 30 months of age corrected for prematurity.

POPULATION

Of 308 surviving children born at <or=25 weeks gestation in the United Kingdom and Ireland from March to December 1995, 283 (92%) were evaluated at 30 months of age corrected for prematurity.

METHODS

Cerebral palsy, severe motor disability, and Bayley scores were used as dependent variables in sequential multiple regression analyses to identify factors associated with adverse outcomes.

RESULTS

Adverse outcomes were consistently more common in boys. Factors related to perinatal illness, ultrasound evidence of brain injury, and treatment (particularly postnatal steroids) were associated with adverse motor outcomes (cerebral palsy, disability or Bayley psychomotor development index). Increasing duration of postnatal steroid treatment was associated with poor motor outcomes. A score was developed for severe motor disability with good negative predictive value. In contrast, mental development was associated with a broader range of factors: ethnic group, maternal educational level, the use of antenatal steroids, and prolonged rupture of membranes in addition to chronic lung disease.

CONCLUSION

Male sex is a pervasive risk factor for poor outcome at extremely low gestations. Avoidable or effective treatment factors are identified, which may indicate the potential for improving outcome.

The EPICure study: growth and associated problems in children born at 25 weeks of gestational age or less

AIM

To define growth outcomes of a geographically defined population of extremely preterm babies.

POPULATION

The EPICure study identified all surviving children in the United Kingdom and Ireland born at < or = 25 weeks 6 days gestation between March and December 1995. Of 308 survivors, 283 (92%) were evaluated at 30 months of age corrected for prematurity.

METHODS

Growth was measured as part of a medical and full neurodevelopmental assessment. Growth parameters were evaluated in relation to other 30 month outcomes and perinatal variables.

RESULTS

The children were smaller in each of the five growth measures compared with published population norms: mean (SD) standard deviation scores were -1.19 (1.32) for weight, -1.40 (1.37) for head circumference, -0.70 (1.19) for height, -1.00 (1.38) for body mass index, and -0.75 (0.95) for mid-upper arm circumference. Despite being of average size at birth, children were significantly lighter with smaller head circumferences at the expected date of delivery, compared with population norms, and only weight showed later catch up, by 0.5 SD. Poorer growth was found in children whose parents reported feeding problems and with longer duration of oxygen dependency, as a marker for neonatal respiratory illness. Although severe motor disability was associated with smaller head circumference, overall there was no relation between Bayley scores and head growth.

CONCLUSIONS

Poor growth in early childhood is common in extremely preterm children, particularly when prolonged courses of systemic steroids have been given for chronic lung disease. Improving early growth must be a priority for clinical care.

A comparison of mid upper arm circumference, body mass index and weight loss as indices of undernutrition in acutely hospitalized patients

A nutritional supplementation trial (Vlaming et al., Clin Nutr 2001; 20: 517) enabled us to assess the nutrition of 1561 patients on emergency admission to hospital. Patients acutely admitted to the 15 relevant medical, surgical and orthopaedic wards were identified. Mid upper arm circumference (MUAC) measurements were obtained in 95% (848 m, 635f) patients. For clinical reasons, Body mass index (BMI) was assessable in only 44% patients (408 m, 285f). Data on three month weight loss were obtainable in 509 patients. These measurements combined to demonstrate that 18.3% of patients were undernourished (At least one of : BMI<20 kg/m(2) or MUAC<25 cm or loss of weight > or =10%). There was a close relationship between BMI and MUAC. Regression equations (excluding age)were for men : BMI=1.01 x MUAC-4.7, (R(2)=0.76), and for women BMI=1.10 x MUAC-6.7, (R(2)=0.76). After adjustment for age, weight loss > or =10% was the most significant of the three as a predictor of mortality. Among patients in whom weight loss was not recorded MUAC was a significant predictor of mortality either alone (P=0.002) or after adjustment for BMI (P=0.007), but BMI was not significant. All three measures, even when adjusted for age and sex, were poor predictors of hospital stay although MUAC was significant in the larger group with a MUAC measure (R(2)=0.7% P<0.001). MUAC correlates closely with BMI, is easier to measure and predicts poor outcome better.

Quantitative studies of the vasculature of the carotid body in the chronically hypoxic rat

The carotid bodies of rats made chronically hypoxic by breathing 12% O2 in a normobaric chamber (inspired PO2 91 mmHg) were compared with those of controls. Serial 5-microm sections of the organs were examined using an interactive image analysis system. The total volume of the carotid bodies was increased by 64%. The total vascular volume rose by 103% and was likely due to an increase in size of the large vessels (>12 microm lumen diameter) because the small vessel (5-12 microm lumen diameter) volume did not increase significantly while the small vessel density tended to decrease. The extravascular volume was increased by 57%. Expressed as a percentage of the total volume of the organ, the total vascular volume did not change, but the small vessel volume was significantly decreased from 7.83 to 6.06%. The large vessel volume must therefore have been increased. The proportion occupied by the extravascular volume was virtually unchanged (84 vs 82%). In accordance with these findings, the small vessel endothelial surface area per unit carotid body volume was diminished from 95.2 to 76.5 mm-1, while the extravascular area per small vessel was increased from 493 to 641 microm(2) or by 30%. In conclusion, the enlargement of the carotid body in chronic hypoxia is most likely due to an increase in total vascular volume, mainly involving the "large" vessels, and to an increase in extravascular volume. This is in contrast to our previously published findings indicating that in the spontaneous insulin-dependent diabetic rat the enlargement of the carotid body is due solely to an increase in extravascular volume.

The carotid body of the spontaneous insulin-dependent diabetic rat

The carotid bodies from adult spontaneous insulin-dependent diabetic rats (strain BB/S) were perfusion-fixed at normal arterial blood pressure with 3% phosphate-buffered glutaraldehyde and compared with the organs from control rats (strain BB/Sc) prepared in the same way. Serial 5-micron sections were cut, stained, and using an interactive image analysis system, were analysed to determine the volumes of the carotid body and its vascular and extravascular compartments. There was no evidence of systemic arterial disease in the carotid stem arteries in either group of animals, and the microvasculature of the organs appeared normal by light microscopy. The volume of the carotid body was unchanged 3 months after the onset of diabetes but was increased at 6 months. The total vascular volume of the organ was unchanged, but the volume of the small vessels (5-12 microns) was increased. In the control group the small vessels comprised 5% of the total volume of the carotid body, or about 44% of the vascular compartment. The percentage of small vessels increased at 3 months in the diabetic group, but had returned to normal at 6 months. The extravascular volume followed the same pattern as the total carotid body volume and so did not change appreciably when expressed as a percentage of the total volume of the organ. The increase in size of the carotid body in diabetic rats is due, therefore, to an augmented extravascular volume. In one diabetic specimen the carotid sinus nerve showed signs of diabetic neuropathy, axonal swelling and intramyelinic oedema. The clinical implications of these results are discussed.

Herpes virus in an obstetric hospital: I: Herpetic eruptions

In a one-year prospective study, 199 of 347 (34%) staff members in direct contact with patients reported 165 non-genital herpes simplex virus (HSV) infections. The mean working time lost due to these infections was 4.7 days (aggregate, 778 days for the year). Serum antibody titre was not significantly associated with the recurrence rate or the duration of infection. A comparison was made of the ethnic, social and environmental histories of staff members prone to HSV infections and of seronegative staff members with no record of cold sores. The absence of effective treatment at present is noted.