Lymphocyte subsets in human immunodeficiency virus type 1-infected and uninfected children in Nairobi

BACKGROUND: Reference lymphocyte subset values for African children are lacking. This study documents these values as well as their alterations associated with perinatal and postnatal HIV-1 transmission and with protection from HIV-1 infection. METHODS: Lymphocyte subsets were determined for HIV-1-seronegative nonpregnant women and their children (controls) and for uninfected, perinatally infected and postnatally infected children born to HIV-1-seropositive mothers in Nairobi, Kenya. The mean, median and 5th and 95th percentile values for CD4+ and CD8+ lymphocyte counts and percentages were determined and compared at the age ranges birth to 3 months, 4 months to 1 year, yearly from 1 to 5 years and from 6 to 10 years of age. RESULTS: Among control children counts differed from published values of other populations. In all age ranges, whereas the absolute values were significantly higher than adult values, the percentages were significantly lower. Children perinatally infected with HIV-1 had clearly distinguishable differences in lymphocyte subset percentages by 3 months of age, when the median CD4+ percentage was 27.9% (5th to 95th percentile, 25.7 to 30.1%) for infected vs. 35.9% (33.3 to 38.7%) for uninfected and 39.9% (37.8 to 42.2%) for control children, P < 0.001; whereas the median CD8+ percentage was 37.0% (33.1 to 41.0%) for infected vs. 27.5% (24.2 to 30.8%) for uninfected and 27.5% (24.2 to 30.8%) for control children, P = 0.001. Differences between uninfected and control children disappeared after 1 year of age. CONCLUSIONS: Normal lymphocyte subset values among African children differ from those in other populations. Significant differences are detectable by 3 months of age in CD4+ and CD8+ lymphocyte percentages among perinatally infected infants, which may be useful as an adjunct in diagnosis. Transient differences observed among HIV-1-exposed but uninfected infants could reflect a successful immune response to HIV-1 challenge.     

儿童原发性免疫缺陷病的免疫学改变及分析

目的了解儿童原发性免疫缺陷病(PID)患儿的实验室免疫检查特点,为临床早期诊断PID提供依据。方法对76例PID患儿的免疫学检查包括细胞免疫和体液免疫指标进行回顾性总结及分析。结果体液免疫检查中,普通变异型免疫缺陷病(CVID)及联合免疫缺陷病的IgG均降低,尤以CVID降低更为明显,且伴IgA及CD19+B细胞明显降低;IgA降低主要见于CVID、选择性IgA缺乏症(IgAD)及共济失调毛细血管扩张症(AT);低丙种球蛋白血症患儿IgG、IgA及CD19+B细胞均降低。细胞免疫功能中CD3+、CD4+T细胞降低主要见于细胞免疫缺陷病、联合免疫缺陷病及DiGeorge综合征(DGS);AT患儿的CD4+/CD8+比例也降低。8例CVID患儿检测T细胞功能亚群及活化指标,其中5例患儿的CD4+/CD8+比例倒置(CD4+/CD8+<0.9);与对照组相比,CVID患儿的CD4+HLA-DR+和CD8+CD45RO+T细胞比例明显升高,CD4+CD45RA+T细胞比例明显降低(P均<0.01)。结论儿童原发性免疫缺陷病免疫学改变各异。CVID患者体内T细胞过度活化,可能是CVID患者容易罹患自身免疫性疾病的原因之一。     

Prognostic significance of immunologic changes in 675 infants perinatally exposed to human immunodeficiency virus. The Italian Register for Human Immunodeficiency Virus Infection in Children.

Neutrophil, lymphocyte, and T-cell subset numbers and immunoglobulin levels were evaluated at birth to age 2 years in 675 children born to mothers infected with the human immunodeficiency virus type 1 (58 infected symptom-free subjects (P-1), 203 infected subjects with symptoms (P-2), and 414 uninfected subjects). The P-2 patients had (even at birth to age 1 month) lower CD4+ lymphocyte and higher IgA and IgM values than P-1 and uninfected children had. Increased IgG values (from 1 to 6 months of age) and increased CD8+ lymphocyte numbers (at 13 to 24 months of age) were also observed. The P-1 children differed from uninfected children only at 13 to 24 months of age (decreased CD4+ and increased CD8+ lymphocytes). Progressive immunologic changes were found in P-2 patients who had severe clinical conditions and in those who died. To evaluate the predictive meaning of the immunologic changes, we selected 164 children (25 P-2, 15 P-1, and 124 uninfected children) because they had been examined sequentially from birth and they were classified as in the indeterminate state of infection (P-0) at immunologic evaluations at birth to age 1 and at 1 to 6 months of age. During the 1- to 6-month period, P-2 patients had higher immunoglobulin and lower CD4+ lymphocyte values than P-1 and uninfected children had; no difference was found between P-1 and uninfected subjects. These results indicate that in infants with perinatal human immunodeficiency virus type 1 infection, immunologic abnormalities correlate with the clinical condition and are predictive of the clinical outcome rather than the infection status.     

CD4 status and P24 antigenemia. Are they useful predictors of survival in HIV-infected children receiving antiretroviral therapy?

OBJECTIVE--To determine the relationship between CD4 status and the P24 antigen level and survival in children infected with the human immunodeficiency virus. DESIGN--Cohort, case-control. SETTING--Clinical Center at the National Institutes of Health, Bethesda, Md. PARTICIPANTS--One hundred forty-seven children infected with the human immunodeficiency virus enrolled in antiretroviral therapy protocols at the National Cancer Institute were reviewed and the relationships between CD4 counts, P24 antigenemia, and death were analyzed. INTERVENTIONS--None. MEASUREMENTS/MAIN RESULTS--The presence of a very low CD count, less than 21% of the lower limit of normal values for age (equivalent to 0.05 x 10(9)/L in an adult), was associated with a significantly increased risk of death within 2 years. Although the risk of death was highest for children with CD4 counts below this level and who had detectable P24 antigen levels, P24 antigenemia by itself contributed little to the prognostic value of the CD4 count alone. However, it was also notable that a group of children with low CD4 counts also experienced prolonged survival. CONCLUSIONS--The association between low CD4 counts and death suggests that the age-adjusted CD4 count should be used as a marker to guide therapeutic intervention. At the same time, the presence of a very low CD4 count alone should not be considered a reason for therapeutic nihilism.     

Immunological evaluation of 60 children with AIDS

OBJECTIVE: The immunologic defects that occur in children with HIV infection are important tests to both diagnosis and therapeutic response. The objective of this study was to verify the immunologic abnormalities in 60 children with AIDS, in Florianópolis, Santa Catarina State, Brazil. METHODS: Serum immunoglobulin levels were determined by nephelometry and compared to a normal pattern for Brazilian children. The lymphocyte T helper (CD4+) and the lymphocyte T suppressor (CD8+) count and percentage, and the ratio between them, determined by commercial flow cytometry, were compared to a pattern for healthy children of HIV-positive mothers. RESULTS: The mean serum IgG levels was higher in the children with AIDS (p<0.005). The mean serum IgM levels was higher in the children with AIDS in the age group between 13 and 108 months (p<0.005). The CD4+ lymphocytes count was below the inferior limit of the 95% confidence interval of the median reference values to each group of age in 50 (84.7%) of the 59 determinations. The CD4+ lymphocytes percentage was much lower than the percentages of reference. The graph curve of the medians of the ratio between lymphocytes CD4+ and CD8+ to each group of age was below the fifth percentile of the graph curve of the medians of reference. CONCLUSIONS: The hypergamaglobulinemia and the lymphocyte T CD4+ count and percentage are sensitive indicators of HIV infection, observed in the present study. Immunologic evaluation of the HIV-positive children is recommended, including those younger than 18 months of age.     

CD4+ and CD8+ T-lymphocyte subsets in Zambian children

Age-related changes in lymphocyte subsets in HIV-uninfected Zambian children are described. The total lymphocyte count and numbers of CD4+ and CD8+ T-lymphocytes declined with increasing age, while the percentage of CD4+ and CD8+ T-lymphocytes changed little during childhood. Girls between the ages of 12 and 71 months had a higher percentage of CD4+ T-lymphocytes and a higher CD4:CD8 ratio than did boys of a similar age.     

826例0岁至学龄前健康儿童外周血淋巴细胞亚群分布的调查分析

目的 调查分析0岁至学龄前健康儿童外周血淋巴细胞亚群的分布。方法 826例0岁至学龄前汉族儿童分为新生儿组、婴儿组、幼儿组、学龄前组,使用流式细胞术检测各组外周血淋巴细胞亚群。结果 CD3⁺细胞、CD3⁺CD4⁺细胞、CD3^-CD19⁺细胞和CD4⁺/CD8⁺在0岁至学龄前儿童不同性别之间的差异具有统计学意义（P < 0.05）,CD3^-CD19⁺细胞以女童较低,其他3个指标以女童较高;CD3⁺、CD3⁺CD4⁺及CD4⁺/CD8⁺均以新生儿组最高,其中CD3⁺CD4⁺及CD4⁺/CD8⁺含量随年龄增长逐渐降低,至学龄前最低（P < 0.05）;CD3^-CD19⁺和CD3^-CD16⁺CD56⁺细胞含量以新生儿组最低,随年龄增长而增高,CD3^-CD16⁺CD56⁺细胞以学龄前组最高,而CD3^-CD19⁺细胞含量在幼儿期达峰值后降低（P < 0.05）;CD3⁺CD8⁺细胞含量以学龄前组最高（P < 0.05）。不同年龄组男童的淋巴细胞亚群分布的变化趋势与不同年龄组儿童的规律一致;在女童中,CD3⁺CD4⁺及CD4⁺/CD8⁺含量也是以新生儿组最高（P < 0.05）。结论 淋巴细胞亚群在不同年龄、性别健康儿童之间的分布不同,建议按年龄、性别分别建立参考值。     

Micronutrients and T-cell subsets: a comparison between HIV-infected and uninfected, severely malnourished Rwandan children

OBJECTIVE: To determine the levels of CD4+ cells and micronutrients in HIV-infected and uninfected severely malnourished children. DESIGN: Cross-sectional study in two centres. SETTING: Children admitted to the malnutrition units in Kigali and Butare, Rwanda. PATIENTS: A total of 112 children aged 2 months to 5 years presenting with severe malnutrition (weight for height Z- score -3 SD +/- oedema). Fifty-two (46.4%) were HIV-infected. METHODS: CD4+ counts, selenium, zinc and copper levels were measured. The percentage of CD4 cells was calculated as a proportion of total lymphocyte count. RESULTS: The mean age of the 52 HIV-infected children (18 months) was lower than of the 60 uninfected children (26 months) (p=0.01). Six (11.5%) of the HIV-infected had oedematous malnutrition compared with 50% of the uninfected group. The mean (SD) CD4+ count was 1054 (780) in the HIV-infected and 1579 (721) in the uninfected group (p=0.001). The CD4+ count was also significantly lower in the HIV-infected group than in the uninfected group for the ages <12 mths (p=0.09), 12-24 mths (p=0.045) and >36 mths (p=0.001). In HIV-infected children, 17% had severe immunosuppression (<15% CD4+ cells), 33% moderate (15-24%) and 50% had none (>25%) compared with 9%, 12% and 80% in the HIV-uninfected group, respectively (p<0.001). Approximately one-third in both groups had low levels of selenium and zinc and 77% had raised levels of copper. In multivariate analysis there was significant correlation between selenium and CD4+ (r=0.36, p<0.001) in HIV-infected children and no correlation of zinc and copper to CD4+ %. In HIV uninfected children, CD4+ % was related to selenium (r=0.282, p=0.03) and to zinc (r=0.264, p=0.047) but not to copper. CONCLUSIONS: In severely malnourished children with HIV infection, low CD4+ levels are associated mainly with HIV infection. There was no significant difference in levels of selenium, zinc and copper between HIV-infected and uninfected children.     

肺炎支原体感染患儿T淋巴细胞亚群检测及分析

目的　观察肺炎支原体肺炎患儿急性期外周血T淋巴细胞亚群、T淋巴细胞活化状态的改变,探讨其发病机制。方法　采用流式细胞仪技术检测了2 0 0 2年1 0月至2 0 0 3年6月就诊于上海市金山区中心医院的1 7例肺炎支原体肺炎患儿急性期外周血T淋巴细胞亚群及T细胞亚群上CD2 5+的表达和CD4+细胞上CD4+CD45RA+、CD4+CD45RO+的表达;对照组为1 0例健康体检儿童。两组年龄、性别差异无显著意义。结果　肺炎支原体肺炎患儿急性期外周血CD3 +百分率( % )为( 62 . 2 3±6 .2 7) ,较对照组( 68 .60±4. 74)低,差异有显著性意义(P <0 . 0 5) ;CD4+、CD8+百分率较对照组差异无显著性意义(P >0. 0 5) ;CD8+CD2 5+百分率( % )为( 0 . 61±0 . 58) ,较对照组( 2 .1 6±0 . 40 )降低,差异有极显著性意义(P <0 .0 1 ) ;CD4+CD45RA+/CD4+CD45RO+比值与对照组相比降低(P <0 . 0 5)。结论　肺炎支原体肺炎时存在细胞免疫失调,主要表现为总T细胞降低,T细胞活化障碍和CD4+CD45RA+/CD4+CD45RO+平衡失调。     

Peripheral blood lymphocyte subsets in healthy Turkish children

Immunophenotyping of peripheral blood lymphocyte subpopulations is essential for the diagnosis and follow-up of children with immunodeficiencies and other immune disorders. The relative size and absolute number distributions (median and 5-95%) of lymphocyte subsets, including cord blood (Coulter, EPICS-XL) were examined by flow cytometry in 190 healthy subjects from birth to 18 years of age with a view to obtaining normal reference values for Turkish children of the following age groups: cord blood (n:29), birth to 1 year (n:41), 1 to 2 years (n:30), 2 to 6 years (n:30), 6 to 10 years (n:30), and 10 to 18 years (n:30). The relative size of CD2+, CD3+CD16-56-, CD3+CD8+ T lymphocytes increased while the relative size and absolute counts of those together with CD3+CD4+ and CD19+, CD20+ B lymphocytes decreased with age. The percentage of CD3-CD16+56+ NK cells increased from 0-1 year to 10-18 years; however, absolute count of CD3-CD16+56+ NK cells remained stable and unchanged in all age groups. The relative size and absolute count of activation markers (CD3+CD25+ and HLADR+) decreased from 0-1 year through 10-18 years age group. This study has once more demonstrated that both the percentage and the absolute number of lymphocyte subsets in cord blood and peripheral blood of healthy infants and children changed with age. Therefore, comparison of results to those of age-matched healthy controls is of utmost importance in the reliable and accurate evaluation of lymphocyte subsets reflecting cellular immunity in children.     

流式细胞术建立甘肃地区学龄前汉族儿童外周血淋巴细胞亚群相对计数的正常参考值范围

目的 建立甘肃地区学龄前汉族儿童外周血淋巴细胞亚群相对计数的正常参考值范围。方法 纳入2018年1月31日至2019年1月30日在甘肃省妇幼保健院(我院)行鞘膜积液、疝、血管瘤等手术或常规体检的0~7岁汉族健康儿童,排除患心脑血管疾病、血常规或肝肾功能异常、行淋巴细胞亚群检测前3周内存在感染、有先天性免疫缺陷疾病者。分为新生儿组、婴儿组、幼儿组和学龄前组。均采集静脉血2 mL(EDTA抗凝),于24 h内用四色荧光标记流式细胞术完成淋巴细胞亚群检测,以(P_2.5,P_97.5)作为各指标的正常参考值范围。结果 ①共792名儿童进入本文分析,男472名,女320名,新生儿组174名、婴儿组216名、幼儿组170名、学龄前组232名。②不同性别之间比较,新生儿组CD4⁺T细胞、CD8⁺T细胞、B细胞、NK细胞百分比和CD4⁺/CD8⁺比值差异有统计学意义,婴儿组CD4⁺T细胞、CD8⁺T细胞、B细胞百分比和CD4⁺/CD8⁺比值差异有统计学意义,学龄前组T细胞、CD4⁺T细胞、B细胞、NK细胞百分比差异有统计学意义。③男、女各年龄组组间整体比较,淋巴细胞亚群百分比差异均有统计学意义。T细胞、CD4⁺T细胞百分比随年龄增长呈降低趋势,男女童降低趋势相近;CD8⁺T细胞百分比随年龄增长呈升高趋势,女童增高趋势更明显;B细胞百分比在1岁前呈上升趋势,后呈降低趋势,女童的变化趋势较为缓和;NK细胞的变化与B细胞相反,在1岁内降低,而后升高,男童变化趋势更明显。结论 健康儿童淋巴细胞亚群的分布与地域、年龄段和性别有关。     

Predicting risk of Pneumocystis carinii pneumonia in human immunodeficiency virus-infected children.

Effective prophylaxis exists against Pneumocystis carinii pneumonia, a major cause of illness and death among human immunodeficiency virus-infected children and adults. While adults with CD4 counts less than 0.2 x 10(9)/L are at highest risk for Pneumocystis carinii, clinical or laboratory markers of high risk in children infected with the human immunodeficiency virus have not yet been established. A chart review of 13 infants with perinatally acquired human immunodeficiency virus infection and children with Pneumocystis carinii pneumonia revealed that infants younger than 12 months developed Pneumocystis carinii pneumonia despite CD4 counts that were normal by adult standards. In contrast to the markedly increased serum IgG levels seen in most children infected with the human immunodeficiency virus, five children with Pneumocystis carinii pneumonia had IgG levels less than 3.0 g/L. Twelve patients had pre-existing symptoms consistent with human immunodeficiency virus infection before the episode of Pneumocystis carinii pneumonia. In addition to clinical symptoms, low IgG levels and CD4 counts adjusted for age may serve to identify those children who are most at risk for Pneumocystis carinii pneumonia and therefore candidates for prophylaxis. Prophylaxis should be offered to all infants under age 12 months with proven, or clinical symptoms compatible with, human immunodeficiency virus infection. For children older than 12 months, CD4 counts less than 0.3 x 10(9)/L appear to be predictive of risk for Pneumocystis carinii pneumonia, and these children should also receive prophylaxis.     

流式细胞术建立甘肃地区学龄前汉族儿童外周血淋巴细胞亚群相对计数的正常参考值范围

目的 建立甘肃地区学龄前汉族儿童外周血淋巴细胞亚群相对计数的正常参考值范围。方法 纳入2018年1月31日至2019年1月30日在甘肃省妇幼保健院(我院)行鞘膜积液、疝、血管瘤等手术或常规体检的0~7岁汉族健康儿童,排除患心脑血管疾病、血常规或肝肾功能异常、行淋巴细胞亚群检测前3周内存在感染、有先天性免疫缺陷疾病者。分为新生儿组、婴儿组、幼儿组和学龄前组。均采集静脉血2 mL(EDTA抗凝),于24 h内用四色荧光标记流式细胞术完成淋巴细胞亚群检测,以(P_2.5,P_97.5)作为各指标的正常参考值范围。结果 ①共792名儿童进入本文分析,男472名,女320名,新生儿组174名、婴儿组216名、幼儿组170名、学龄前组232名。②不同性别之间比较,新生儿组CD4⁺T细胞、CD8⁺T细胞、B细胞、NK细胞百分比和CD4⁺/CD8⁺比值差异有统计学意义,婴儿组CD4⁺T细胞、CD8⁺T细胞、B细胞百分比和CD4⁺/CD8⁺比值差异有统计学意义,学龄前组T细胞、CD4⁺T细胞、B细胞、NK细胞百分比差异有统计学意义。③男、女各年龄组组间整体比较,淋巴细胞亚群百分比差异均有统计学意义。T细胞、CD4⁺T细胞百分比随年龄增长呈降低趋势,男女童降低趋势相近;CD8⁺T细胞百分比随年龄增长呈升高趋势,女童增高趋势更明显;B细胞百分比在1岁前呈上升趋势,后呈降低趋势,女童的变化趋势较为缓和;NK细胞的变化与B细胞相反,在1岁内降低,而后升高,男童变化趋势更明显。结论 健康儿童淋巴细胞亚群的分布与地域、年龄段和性别有关。     

365��̫ԭ��ѧ��ǰ��ͯ�ܰ�ϸ����Ⱥ�������

??Abstract??Objective To establish the reference ranges for normal values of peripheral blood lymphocyte subsets in healthy Shanxi children of preschool age. Methods Healthy children aged 3-6 in Taiyuan of shanxi province were enrolled in the study. Relative counts and absolute counts of lymphocyte subpopulations of T cell?? CD3+ CD19-????CD4+ T cell ?? CD3+ CD4+????CD8+ T cell?? CD3+ CD8+????B cell?? CD3- CD19+?? and NK cell?? CD3- CD16+ CD56+?? were detected by three-color flow cytometric analysis. Peripheral blood lymphocyte subsets percentage and absolute counts of lymphocyte subsets in peripheral blood of healthy preschoolers and CD4+ /CD8+ were analyzed?? differences of which were compared between male and female. Results The percentages and absolute values of T cell??CD4+ T cell??CD8+ T cell??B cell and NK cell had no statistically significant difference between the genders ??P??0.05?? in 365 healthy preschoolers. The reference ranges for normal values of T cell??CD4+ T cell??CD8+ T cell??B cell and NK cell respectively were 43.8%??80.3% ??1563??3929 cells/μL????18.8%??46.7% ??738??2001 cells /μL????13.9%??36.1% ??5 32??1549 cells/μL????8.5%??24.6% ??261??960 cells/μL ????4.9%??24.6% ??197??786 cells /μL?? and CD4+ /CD8+ was 0.71??2.39. Conclusion It is important and necessary to establish the normal reference values of peripheral blood lymphocyte subsets for healthy children in the same race and district.It's shown here that there is no statistical difference in the peripheral blood lymphocyte subpopulation distribution between male and female in healthy preschool children.     

Age-related standards for total lymphocyte, CD4+ and CD8+ T cell counts in children born in Europe

OBJECTIVE: Currently used reference values for immunologic markers in children are largely derived from cross-sectional data from historic, small sample size studies in predominantly white children. There is a lack of reliable age-related standards for immunologic markers, such as CD4+ cell counts, in particular in black children whose values according to recent reports may differ from those in white children. Standards are essential for diagnosing and monitoring childhood diseases such as pediatric human immunodeficiency virus (HIV) infection. DESIGN: Prospective cohort study with data on 1781 uninfected children born to HIV-infected mothers in the European Collaborative Study. METHODS: Age-related standards (centiles) for immunologic markers (CD4+ and CD8+ cell counts and total lymphocyte counts) up to 5 years in black and up to 10 years in white children were constructed using Generalized Additive Models for Location, Scale and Shape method, which allows for variability and skewness of the data. The optimal model was chosen according to the Akaike Information Criterion. RESULTS: Patterns and values of total lymphocyte, CD4+ and CD8+ cell counts varied with age, especially in the first 3 years of life, but less so thereafter. Values of all 3 immunologic markers were substantially and significantly lower in black than in white children of the same age. CONCLUSIONS: We present age-related standards separately for black and white children to aid clinicians in the monitoring of childhood diseases. These standards may also contribute to the decision on an accurate cutoff for CD4+ cell counts for initiating treatment of HIV-infected children.     

Risk factors for opportunistic illnesses in children with human immunodeficiency virus in the era of highly active antiretroviral therapy

OBJECTIVE: To examine the relationship between the use of highly active antiretroviral treatment (HAART) and the occurrence of opportunistic illnesses (OIs) among children perinatally infected with human immunodeficiency virus. DESIGN: Prospective cohort study. SETTING: Pediatric AIDS Clinical Trials Group 219C cohort. PARTICIPANTS: From September 15, 2000, to August 31, 2003, 1927 children perinatally infected with human immunodeficiency virus and receiving HAART were followed up.Main Exposures Age at initiating HAART, duration of HAART use, CD4+ T-lymphocyte percentage, and human immunodeficiency virus 1 viral load. MAIN OUTCOME MEASURES: Incidence rates for Centers for Disease Control and Prevention OI category B and OI category C events were calculated. The association between main exposures and OI occurrence was estimated using proportional hazards regression. RESULTS: Of 1927 subjects, 226 (12.7%) developed OIs during follow-up. Incidence rates were 4.99 per 100 person-years (95% confidence interval, 4.30-5.76) for first OI category B events and 1.47 per 100 person-years (95% confidence interval, 1.12-1.91) for first OI category C events. Duration of HAART use was not related to OI risk. Older age (age >10 years) at HAART initiation was associated with increased risk of a first OI (hazard ratio, 2.48; 95% confidence interval, 1.23-5.00) compared with initiating HAART in children younger than 2 years. This increased risk diminished after adjusting for CD4+ T-lymphocyte percentage and Centers for Disease Control and Prevention disease category at HAART initiation. More children with OIs than without OIs had a CD4+ T-lymphocyte percentage of less than 15% at HAART initiation (49.6% of children with OIs vs 23.7% of children without OIs), at enrollment (41.2% of children with OIs vs 7.7% of children without OIs), and at the end of follow-up (41.2% of children with OIs vs 8.3% of children without OIs). CONCLUSIONS: Opportunistic illnesses are occurring in the pediatric human immunodeficiency virus population in the HAART era, mainly in children with persistently low CD4+ T-lymphocyte percentages. Lack of a sustained response to HAART rather than age at or duration of HAART use is predictive of OI risk.     

Growth hormone in T-lymphocyte thymic and postthymic development: a study in HIV-infected children

OBJECTIVES: Growth hormone (GH) plays a role in thymic function, and recombinant GH may stimulate thymopoiesis in HIV-infected individuals. We performed immunologic analyses in 26 antiretroviral-treated children matched for age, pubertal status, clinical parameters, and antiretroviral exposure who did or did not show an impaired response to GH-release stimulation tests with arginine + GH-releasing hormone. RESULTS: The following abnormalities were found in GH-deficient compared with GH-nondeficient children after >4 years of therapy: CD4 count ( P = .02) and percentage ( P = .03), CD4 as percentage of normal cells for age ( P = .003), serum interleukin-7 concentration ( P = .02), and thymic volume ( P = .01). Naive CD4 (4+62+RA+ and 4+CCR7+RA+) and CD8 (8+CCR7+RA+) lymphocytes were lower in GH-deficient children ( P = .003; P = .007; and P = .02, respectively). Postthymic pathways were also impaired in GH-deficient children. Thus, central memory (4+CCR7+RA-) CD4+ cells were reduced ( P = .006), whereas effector memory (4+CCR7-RA-) CD4+ cells ( P = .002) and late effector CD8+ lymphocytes (8+CCR7-RA+ and 8+27-28-) ( P = .009 and P = .002, respectively) were increased in these children. CONCLUSIONS: Growth hormone plays a role in thymic and postthymic pathways, and defective GH production may be associated with incomplete immunoreconstitution. Immunomodulant agents (including GH) could be useful in patients with defective GH production.     

Natural history of HIV infected pediatric long-term or slow progressor population after the first decade of life

BACKGROUND: Perinatally infected long-term nonprogressors/slow progressors represent a select group of individuals. There is very limited information on this group of children beyond the first decade of life. A group of HIV-infected long-term nonprogressor/slow progressor children was studied. METHODS: We enrolled 20 HIV-infected adolescents who were receiving no or minimal therapy (defined as single or dual nucleoside therapy) before the age of 10 years and who had maintained CD4 counts above 25% for the first decade of life. We analyzed immunologic and virologic characteristics. Thymic receptor excision circles (TREC) were measured on stored frozen peripheral blood mononuclear cells. CD4 count, viral load and other pertinent information including race and age were obtained from individual medical records. RESULTS: Nine of the 20 patients recruited were noted to have developed falling CD4 counts at or around puberty, whereas the other 11 remained stable. There was no difference in TREC values or HIV RNA values before or after puberty between the 2 groups of patients. Those who remained stable, in terms of maintaining CD4 T cells as a group had falling viral loads with age. Those whose CD4 values declined after puberty had viral loads that did not decrease with age. CONCLUSION: A select group of patients who never received HAART during their first decade of life will continue to maintain good CD4 associated with declining HIV RNA values. Thymic output is not predictive of those that don't maintain CD4 T cells.     

Hepatitis C prevalence in children with perinatal human immunodeficiency virus infection enrolled in a long-term follow-up protocol

OBJECTIVE: To evaluate the prevalence of hepatitis C virus (HCV) infection in children with perinatal human immunodeficiency virus (HIV) infection. DESIGN: Cross-sectional substudy. SETTING: Multicenter study from 41 sites in the United States. PATIENTS: Children with perinatal HIV infection were randomly selected from a large, long-term, follow-up protocol. MAIN OUTCOME MEASURE: Hepatitis C infection was defined as having positive test results on both HCV antibody and HCV RNA assays. RESULTS: Five hundred thirty children enrolled in the substudy; definitive HCV test results were available for 525 children. Eighty-three percent were of a minority race or ethnicity.They were equally distributed by sex, had a median age of 10.7 years, and were relatively healthy, with 75% having CD4+ lymphocyte counts greater than 500 cells/mm3. Eight of 525 children (1.5%; 95% confidence interval [CI], 0.7%-3.0%) infected with HIV were coinfected with HCV. In contrast, the rate of HCV infection in a serosurvey of more than 2700 children aged 6 to 11 years from the National Health and Nutrition Examination Survey was 0.2% (95% CI, 0.04%-0.6%). In our study, there were no differences between children coinfected with HIV and HCV and those without HCV infection in terms of demographic characteristics, CD4+ or CD8+ T-lymphocyte counts, HIV 1 RNA levels, preterm or mode of delivery, or liver disease; however, the number of children coinfected with HIV and HCV was small. CONCLUSION: While HCV prevalence infection rates are low in children with perinatal HIV infection, they are 8 to 10 times higher than reported in HCV serosurveys of children in the United States.     

Immunological manifestations of HIV-infected children

This cross-sectional study of stable HIV-infected children was designed to document the immunological manifestations of paediatric HIV infection and to determine whether inexpensive markers of immunosuppression could be identified. Investigations included lymphocyte count and subset analysis, levels of total protein, albumin, immunoglobulins, beta-2 microglobulin and neopterin. The median age of the 74 children studied was 16.5 months and 76% and 39% had subnormal percentage CD4+ counts and absolute CD4+ counts, respectively. According to the Centers for Disease Control (CDC) guidelines, 85% were moderately or severely immunosuppressed. The majority had elevated neopterin, beta-2 microglobulin, IgG, IgM and IgA concentrations. The IgG concentration correlated positively with total globulin, IgG1 and IgG3 concentrations. On bivariate analysis, the absolute CD4+ count correlated positively with total lymphocyte count (r = 0.28 < 0.48 < 0.64) and negatively with total IgG concentration (r = -0.47 < -0.27 < -0.04), IgG1 concentration (r = -0.51 < -0.31 < -0.08), and neopterin concentration (r = -0.49 < -0.28 < -0.04). There was no correlation between CD4+ count, total globulin or beta-2 microglobulin concentration. On multiple linear regression analysis only the total lymphocyte count correlated with CD4+ count. Furthermore, on bivariate analysis total lymphocyte count correlated positively with absolute CD8+ count (r = 0.82 < 0.88 < 0.92). In conclusion, although there was a positive correlation between absolute CD4+ count and total lymphocyte count, the clinical significance is questionable as the total lymphocyte count correlated more strongly with the absolute CD8+ count.