Changes in airway configuration with different head and neck positions using magnetic resonance imaging of normal airways: a new concept with possible clinical applications.

BACKGROUND: The sniffing position is often considered optimal for direct laryngoscopy. Another concept of airway configuration involving a laryngeal vestibule axis and two curves has also been suggested. We investigated whether this theory can be supported mathematically and if it supports the sniffing position as being optimal for direct laryngoscopy. METHODS: Magnetic resonance imaging scans were performed in 42 normal adult volunteers. The airway passage was divided into two curves-primary (oro-pharyngeal curve) and secondary (pharyngo-glotto-tracheal curve). Airway configuration was evaluated in the neutral, extension, head lift, and sniffing positions. The airway passage, point of inflection (where the two curves meet), its tangent, and the line of sight were plotted on each scan. RESULTS: The point of inflection lay within the laryngeal vestibule in all positions. The head lift and sniffing positions caused the tangent to the point of inflection to approximate the horizontal plane. The sniffing, extension, and head lift positions caused a reduction in the area between the line of sight and the airway curve compared with the neutral position. CONCLUSIONS: A two-curve theory is proposed as a basis for explaining airway configuration. The changes in these curves with head and neck positioning support the sniffing position as optimal for direct laryngoscopy. Application of this new concept to other forms of laryngoscopy should be investigated.

Disclosure of HIV diagnosis to children: when, where, why, and how.

Despite recent recommendations by the American Academy of Pediatrics that strongly encourage disclosure of human immunodeficiency virus (HIV) infection to school-age children, health care providers vary widely in their actual disclosure practices. Concrete guidelines for accomplishing disclosure are not currently available. Nondisclosure can result in a variety of problems, including anxiety, depression, phobias, and exclusion from peer support groups and medical camps. This article reviews the available literature on disclosure of HIV infection to children and describes the disclosure process used in a large, urban pediatric HIV clinic.

A stable latent reservoir for HIV-1 in resting CD4(+) T lymphocytes in infected children.

HIV-1 persists in a latent state in resting CD4(+) T lymphocytes of infected adults despite prolonged highly active antiretroviral therapy (HAART). To determine whether a latent reservoir for HIV-1 exists in infected children, we performed a quantitative viral culture assay on highly purified resting CD4(+) T cells from 21 children with perinatally acquired infection. Replication-competent HIV-1 was recovered from all 18 children from whom sufficient cells were obtained. The frequency of latently infected resting CD4(+) T cells directly correlated with plasma virus levels, suggesting that in children with ongoing viral replication, most latently infected cells are in the labile preintegration state of latency. However, in each of 7 children who had suppression of viral replication to undetectable levels for 1-3 years on HAART, latent replication-competent HIV-1 persisted with little decay, owing to a stable reservoir of infected cells in the postintegration stage of latency. Drug-resistance mutations generated by previous nonsuppressive regimens persisted in this compartment despite more than 1 year of fully suppressive HAART, rendering untenable the idea of recycling drugs that were part of failed regimens. Thus the latent reservoir for HIV-1 in resting CD4(+) T cells will be a major obstacle to HIV-1 eradication in children.

Children affected by HIV. Clinical experience and research findings.

This article describes the plight of HIV affected children, and the work of mental health professionals with HIV affected children and their families, and presents pertinent research findings on the topics. The concepts of prevention, resilience, and family and child development are applied to the organizing of mental health care for HIV affected children.

Whole body protein turnover in children with human immunodeficiency virus (HIV) infection.

The purpose of this study was to determine the rate of whole body protein turnover (WBPT) in human immunodeficiency virus (HIV)-infected children, and to determine the relationship between WBPT and growth. The rate of WBPT was calculated from the cumulative excretion of labeled urinary ammonia after a single intravenous dose of 15N-glycine in three groups of children: 1) HIV+ with growth retardation (HIV+ Gr); 2) HIV+ with normal growth (HIV+); and 3) HIV-uninfected with normal growth (HIV-). Twenty-six children between 2 and 11 y of age were studied (10 HIV+ Gr, 12 HIV+, 4 HIV-). All children were afebrile and free of acute infection during the study. Rates of WBPT (mean +/- SD) for the study groups were: HIV+ Gr, 12.2 +/- 4.8; HIV+, 10.7 +/- 5.1; and HIV-, 8.6 +/- 2.1 g.protein.kg-1.d-1 (NS, P > 0.05). Although not statistically significant, mean WBPT was 42% greater in HIV+ Gr, and 24% greater in HIV+ compared to HIV-. Statistically significant correlations were found between WBPT and Z scores for height (r = -0.39, P = 0.05) and weight-for-age (r = -0.51, P = 0.01) and dietary intake of protein (r = 0.39, P = 0.05), and between protein balance (synthesis-catabolism) and intakes of energy (r = 0.47, P = 0.02) and protein (r = 0.40, P = 0.04). There was no statistically significant correlation between WBPT and resting energy expenditure (r = 0.27, P = 0.19), or CD4 cell number (r = 0.05, P = 0.82). These data suggest an association between increased rates of protein turnover and low weight and height-for-age Z scores, and that it may be possible to achieve positive protein balance given an adequate intake of nutrients.

Resting energy expenditure and body composition in children with HIV infection.

The purpose of this study was to determine whether alterations in body composition, resting energy expenditure (REE), and dietary energy intake are associated with growth retardation in HIV-positive children. Body composition (deuterium oxide dilution, skinfold measurements), REE (indirect calorimetry), and energy intake (24-hour weighed food intake) were evaluated in three groups: HIV-positive with growth retardation (HIV+Gr), HIV-positive with normal growth (HIV+); and HIV-uninfected with normal growth (HIV-). Children were between 2 and 11 years of age, afebrile, and free from acute infection. Forty-two children (13 HIV+Gr, 19 HIV+, 10 HIV-) were studied. Lean body mass was significantly reduced in HIV+Gr compared with HIV- (p < .05), and fat mass was significantly reduced in HIV+Gr and HIV+ compared with HIV- (p < .05). The percentages of lean and fat mass were not significantly different between groups, suggesting that differences in lean and fat mass were proportional to differences in body size. Consistent with reduced lean body mass, mean REE was significantly lower in HIV+Gr compared with HIV- (p < .05). Differences in mean REE/kg of body weight or lean body mass between groups were not statistically significant. A significant negative correlation was found between REE (kcal/kg/day) and weight-for-age (p = .04), and a trend with height-for-age Z-score (p = .07). Mean energy intake was not significantly different between groups. This study suggests that lean and fat mass are proportionately reduced in HIV-positive children with growth retardation. Further studies are necessary to delineate the relationship between energy balance and growth in children with HIV infection.

Primary care for children with human immunodeficiency virus infection.

Pediatric human immunodeficiency virus (HIV) infection is now the seventh leading cause of death in U.S. children 1 to 14 years of age and the leading cause of death in children 2 to 5 years of age in many U.S. cities. The key to enhancing the quality and duration of life in HIV-infected children is to recognize and diagnose HIV infection as early as possible and to initiate prophylactic and antiretroviral therapies. Most of the medical treatment of these children can be conducted in a primary care setting if (a) primary care practitioners are informed of current treatment regimens and (b) adequate pediatric HIV consultation service is available. This article reviews the primary care of HIV-infected children including early diagnosis, current treatment options, and the complex psychosocial issues associated with caring for these children.

Serum and plasma markers of nutritional status in children infected with the human immunodeficiency virus.

OBJECTIVE: To determine whether reduced serum or plasma protein and micronutrient levels are common in children infected with the human immunodeficiency virus (HIV) and whether these levels are different in children with growth retardation compared to those with normal growth. SUBJECTS: Children were separated into three groups: (a) HIV-infected with growth retardation (HIV + Gr); (b) HIV-infected with normal growth (HIV+); (c) HIV-uninfected with normal growth (HIV-). All children were afebrile and free of acute infection at the time of study. During a 24-hour stay in the Pediatric Clinical Research Unit, blood was drawn for analysis of total protein, albumin, zinc, selenium, and vitamin A levels; growth measurements were obtained; and dietary intake was assessed by 24-hour weighed food intake and 24-hour dietary recall. STATISTICAL ANALYSIS: Mean differences between groups were assessed by analysis of variance, and differences in the frequency of nutrient deficiency were determined by chi 2 analysis. RESULTS: Thirty-eight children between 2 and 11 years of age were studied: 10 HIV + Gr, 18 HIV+, and 10 HIV-. No statistically significantly differences were noted in mean levels of albumin, prealbumin, zinc, and selenium. Mean serum level of vitamin A was significantly higher in the HIV + Gr group than in the other two groups. There were no significant differences between groups in the frequency of deficiency for any nutrient studied. Mean energy and nutrient intake was similar among groups. APPLICATIONS/CONCLUSIONS: Abnormal serum or plasma protein or micronutrient levels were uncommon in this cohort of HIV-infected children, even in children with growth retardation. Routine monitoring of the level of proteins and micronutrients studied is unnecessary in the absence of specific clinical indicators of deficiency.

Impact of on-site social work services on the documentation of client and family-centered information: the experience of Ryan White CARE Act (Title IV) pediatric program sites in Maryland.

BACKGROUND: The purpose of this study is to (1) describe client and maternal demographic, social, and medical characteristics of pediatric clients receiving medical and social services at Ryan White (Title IV) program sites, and (2) determine the impact of on-site social work services in documenting client and family-related information used to assess the psychosocial needs of the families affected by human immunodeficiency syndrome and acquired immunodeficiency syndrome (HIV/AIDS). METHODS: We studied infants born to known HIV-infected women who received HIV-related medical services at a federally funded Title IV Ryan White CARE Act provider site in Maryland. Eligibility criteria included < 24 months of age at time of initial clinic visit, a history of birth to a known HIV-infected woman, and a minimum of one comprehensive clinical visit for medical evaluation at a selected Title IV provider site. Study populations were categorized into three independent clinic cohorts. A pre- and postintervention study design was used to assess the impact of the intervention (i.e., on-site social work activities) on variables of interest. Clinic cohorts were (a) preintervention group (N = 181), from January 1, 1986 to December 31, 1989; (b) initial postintervention group (N = 216), from January 1, 1991 to December 31, 1992; and, (c) long-term postintervention group (N = 197), from January 1, 1993 to March 1, 1994. Client and maternal demographic, social, and medical information were recorded and statistical comparisons between pre- and postintervention clinic cohorts were completed with the use of standard statistical methods. RESULTS: Pediatric clients were predominantly African American (94%), lived in low-income family units reflected by the prevalence of public assistance programs (i.e., Medicaid), had a high likelihood of Medicaid enrollment (> 80%), and reported a high frequency of social disruption (e.g., protective services interventions and housing difficulties). Greater than half of all medical records documented the "mother" as the client's primary caregiver in the three cohorts (a,b,c, above) pre- and postintervention cohorts, 51%, 65%, and 66.5%, respectively. Over two-thirds of the mothers among all cohorts were reported to have a current or past history of illicit drug use or alcohol abuse, 69%, 62%, and 67.5%, respectively. Postintervention groups, both initial and long term, were significantly more likely than the preintervention group to have documented medical record information relevant to a history of protective services, housing problems, and maternal demographic, social, and clinical information. Maternal HIV-related clinical status and select social factors (e.g., drug use, housing) remained underreported in both postintervention groups. CONCLUSIONS: Title IV pediatric clinical sites deliver services to a predominantly urban, poor, minority community-the population at greatest risk for pediatric HIV-infection in Maryland. Alternative family members as the primary caregiver for infants and children was common and increased over time. These findings demonstrate that Title IV funded programs have been successful in the documentation of valuable client and maternal information necessary for the development of family-centered clinical and support services to a highly vulnerable population of HIV at-risk or infected infants and children in Maryland.

Randomized study of the tolerance and efficacy of high- versus low-dose zidovudine in human immunodeficiency virus-infected children with mild to moderate symptoms (AIDS Clinical Trials Group 128). Pediatric AIDS Clinical Trials Group.

The current dosage of zidovudine for children is 180 mg/m2 every 6 h. To investigate whether a lower dosage was equally effective, human immunodeficiency virus (HIV)-infected children (3 months to 12 years) with mild to moderate symptoms were randomly assigned to receive either high-dose (180 mg/m2/dose) or low-dose (90 mg/m2/dose) zidovudine (double-blind). Treatments were compared with respect to neuropsychologic function, survival, clinical and laboratory evidence of disease progression, and safety and tolerance. Four hundred twenty-six HIV-infected children were enrolled; median time for receipt of study drug was 35 months. Zidovudine in either dose was well tolerated, with no difference in efficacy or tolerance by treatment group using any clinical or laboratory parameter. In children with mild to moderate disease, a reduction of zidovudine to 90 mg/m2/dose will result in substantial cost savings and should be the recommended dose.

Chromoblastomycosis caused by Exophiala spinifera.

We report the second case of chromoblastomycosis caused by Exophiala spinifera; this is the first known case in the United States. Examination of biopsied tissue showed thick-walled, internally septated, chestnut brown muriform cells (sclerotic bodies) within multinucleated giant cells present in the dermis that were characteristic of chromoblastomycosis. The individual cells within the muriform cells disarticulated from the outer wall of the parent cell and from each other to form endoconidia within the outer walls of the parent cells. After fracture of the outer walls, the endoconidia were released. This unique process of endoconidial formation in vivo for the propagation of muriform cells was observed for the first time. Initial treatment with itraconazole and 5-fluorocytosine followed by treatment with itraconazole and heat resulted in marked improvement in the patient's lesions. This infection reiterates the fact that the dematiaceous fungus E. spinifera, a well-known etiologic agent of phaeohyphomycosis, can cause more than one type of infection and supports earlier observations that chromoblastomycosis and phaeohyphomycosis represent extremes of a continuum of infections.

Longitudinal assessment of growth in children born to mothers with human immunodeficiency virus infection.

OBJECTIVES: To describe and to evaluate the longitudinal growth of children born to mothers with human immunodeficiency virus (HIV) infection. DESIGN: Measurements of weight, length (measured in infants in a recumbent position) and height (measured in older children in an upright position), and head circumference were documented and evaluated longitudinally using generalized estimating equations in a group of children born to HIV-infected mothers. Children infected with HIV were compared with uninfected children and with National Center for Health Statistics standards. SETTING: Primary care clinic in an urban hospital devoted to the medical care of children born to HIV-infected mothers. PATIENTS: One hundred nine children born to HIV-infected mothers, 59 HIV-infected and 50 uninfected, between birth and 70 months of age. RESULTS: The mean birth weights of both groups were below the 50th percentile. While the mean weight-for-age curve of uninfected children attained the 50th percentile by age 24 months, the mean birth weight-for-age curve of HIV-infected children remained below the 50th percentile. Weight gain became significantly different between the two groups by age 36 months. The mean birth length-for-age curves of HIV-infected and uninfected children was also below the 50th percentile. The mean height-for-age curve of uninfected children attained the 50th percentile by age 40 months, while that of HIV-infected children remained well below the 50th percentile. Linear growth between HIV-infected and uninfected children diverged earlier than weight, becoming significantly different by age 15 months. CONCLUSIONS: Although children born to HIV-infected mothers are born with weight and length below the 50th percentile, uninfected children catch up, while HIV-infected children remain below the 50th percentile and experience an earlier and more pronounced decrease in linear growth (height-for-age) than in weight-for-age.

Human immunodeficiency virus-specific IgA in infants born to human immunodeficiency virus-seropositive women.

OBJECTIVE: To determine the sensitivity and specificity of human immunodeficiency virus (HIV)-specific IgA for vertically transmitted HIV infection, particularly during the first month of life. DESIGN/SETTING/PATIENTS: Prospective cohort study of 140 infants born to HIV-seropositive women in a large urban teaching hospital and of 248 older infants and children referred for diagnosis and treatment of HIV infection. MAIN OUTCOME MEASURES: The HIV-specific IgA immunoblot results were compared with the infection status of patients as determined by Centers for Disease Control and Prevention (Atlanta, Ga) criteria or by sequential early diagnostic assays for HIV. Sensitivity, specificity, and predictive values were calculated for each age range. RESULTS: Among infants studied from birth, the rate of vertical transmission of HIV was 21.6% (25/116). The sensitivity of HIV-specific IgA for the first month of life was 8.0% (2/25), and the specificity was 90.1% (82/91). Sensitivity increased progressively during the first year of life, and the negative predictive value was 94.6% by 6 to 8 months of age. The positive predictive value of this assay was 18.2% for neonates but was 96% to 100% after the first month of life. CONCLUSIONS: False-positive test results for HIV-specific IgA occurred with diminishing frequency during the first 4 weeks of life, and the frequency of detectable HIV-specific IgA was similar among the HIV-infected and uninfected groups at this age. Beyond 1 month of age, detection of HIV-specific IgA is highly specific and is a useful serum-based assay for early diagnosis of HIV infection. These results suggest that maternal-fetal transfusion is common and support the hypothesis that the majority of maternal-fetal transmission of HIV occurs around the time of parturition.

Improved detection of Cryptococcus neoformans in the BACTEC NR 660 blood culture system.

To determine the impact of continuous agitation versus 24 hours agitation on the growth of Cryptococcus neoformans in the BACTEC NR 660 blood culture system, the authors compared recovery and detection time for 50 clinical isolates in Peds Plus, 26 Plus, and Fungal Medium bottles in paired simulated blood cultures. After 144 hours of continuous agitation, the Peds Plus bottle detected 96% of the isolates in an average of 82.5 hours, the 26 Plus bottle detected 96% in 79.5 hours, and the Fungal Medium detected 98% in 81.8 hours. For the bottles that were agitated only for the first 24 hours and incubated motionless for 120 hours (as recommended by the manufacturer), the Fungal Medium detected 82% of the isolates in 100.7 hours. However, the Peds Plus and 26 Plus bottles each detected only 38% of the isolates in an average of 112.4 hours and 109.9 hours, respectively. These results indicate that continuous agitation of BACTEC blood culture bottles for the full incubation time significantly improves (P < or = .0001) the detection and recovery of C neoformans.

Effect of enteral tube feeding on growth of children with symptomatic human immunodeficiency virus infection.

Malnutrition and growth failure are frequent clinical consequences of human immunodeficiency virus (HIV) infection in children. Tube feeding is a means by which to increase the enteral intake of nutrients. We examined the effect of tube feeding in 18 children, median age 6 months (range, 3-159). Tube feedings were initiated due to growth failure in all, which was also associated with dysfunctional swallowing or aspiration in seven children and gastroesophageal reflux in two. Tube feedings were infused via nasogastric tube (n = 4) or gastrostomy tube (n = 14) and were continued for a median of 8.5 months (range, 2-24). Stoma complications developed in three children with gastrostomy tubes; these were the only tube-related side effect. Tube feedings were discontinued due to noncompliance (n = 3), gastrostomy leakage (n = 2), intolerance (n = 2), and death (n = 3). Anthropometric changes were evaluated comparing mean standard deviation scores (Z) before and after tube feeding. Tube feeding resulted in significantly increased weight for age (Z, -2.13 +/- 0.7 vs. -1.46 +/- 1.4; p = 0.04), weight for height (Z, -1.07 +/- 1.0 vs. -0.13 +/- 1.0; p = 0.004), and arm fat area (Z, -1.75 +/- 1.3 vs. -0.62 +/- 1.2; p = 0.01). However, tube feeding did not result in significant changes in height for age (Z, -1.93 +/- 0.8 vs. -1.74 +/- 1.6) or arm muscle area (Z, -1.24 +/- 0.9 vs. -0.57 +/- 1.2). Tube feedings effectively increased the weight of HIV-infected children in this study, but they were not sufficient to correct linear growth deficits.

Acid dissociation of immune complexes improves diagnostic utility of p24 antigen detection in perinatally acquired human immunodeficiency virus infection.

Since acid treatment of serum is known to disrupt immune complexes, the diagnostic utility of the p24 antigen assay was examined after acid treatment of 345 serum samples from 158 children born to women infected with human immunodeficiency virus (HIV). Although the p24 antigen assay after acid treatment was negative in 9 HIV-1-infected children < 1 week old, antigen was detectable at high levels in all 30 samples obtained from infected children 1-9 months old. Overall, antigen was positive in 145 (sensitivity 89.5%) of 162 samples from 47 HIV-1-infected children > or = 1 month old. In contrast, the sensitivity of the p24 antigen assay without acid dissociation was only 18% (P < .001). Among the 76 uninfected children, 132 (specificity 99.2%) of 133 specimens were p24 antigen-negative after acid dissociation. These results demonstrate that acid treatment of serum markedly improves the sensitivity and predictive value of the p24 antigen assay for diagnosis of perinatally acquired HIV-1 infection in children 1 month of age or older.

HIV-infected women and infants. Social and health factors impeding utilization of health care.

The utilization of health care by HIV-seropositive pregnant women and their infants was studied in an indigent urban population. Ninety HIV-seropositive women delivered 99 HIV-exposed infants at the Johns Hopkins Hospital from August 1, 1988, to April 1, 1991. Repeat pregnancies occurred in 17 (18.9%) women during the study period. Completion of the primary immunization series by age nine months was the criteria for infant adherence to medical care. Of all infants, 72.9% achieved adequate immunization status by nine months. However, only 41 (45.6%) women reported ever seeking HIV-related health care. Factors associated with maternal adherence with HIV-related health care included HIV status of her infant, maternal drug use, and incarceration. Number of living children, maternal age, educational level, marital status, and repeat pregnancy were not associated with mothers seeking HIV-related health care. Despite low adherence to HIV-related health care in this sample of HIV-seropositive women, the majority of their infants did receive adequate immunizations, one proxy measure of adequate infant health care.