Invasive pneumococcal infections in human immunodeficiency virus-infected children

Mortality and its association with CD4 cell count and hemoglobin level among children on antiretroviral therapy in Ethiopia: a systematic review and meta-analysis

Background

Even though there are advancements in HIV/AIDS prevention and treatment approach, HIV continues to be a global challenge. Pediatrics HIV is one of the challenges in the reduction of child mortality particularly in less developed countries like Ethiopia. Therefore, this study aims to estimate the pooled proportion of child mortality and the effect of hemoglobin level and CD4 cell count among children on antiretroviral therapy in Ethiopia.

Method

All published were articles searched using PubMed, EMBASE, Google Scholar, and Web of Science database. Besides, Ethiopian institutional research repositories and reference lists of included studies were used. We limited the searching to studies conducted in Ethiopia and written in the English language. Studies that were done in a cohort, cross-sectional, and case-control study design were considered for the review. The weighted inverse variance random effects model was applied, and the overall variations between studies were checked by using heterogeneity test Higgins’s (I²). Subgroup analysis by region and year of publication was conducted. All of the included articles were assessed using the Joanna Briggs Institute (JBI) quality appraisal criteria. In addition, publication bias was also checked with Egger’s regression test and the funnel plot. Based on the results, trim and fill analysis was performed to manage the publication bias.

Result

A total of 16 studies with 7047 participants were included in this systematic review and meta-analysis. The overall pooled proportion of mortality among children on antiretroviral therapy (ART) was found to be 11.78% (95% CI 9.34, 14.23). In subgroup analysis, the highest child mortality was observed in the Amhara region 16.76 % (95% CI 9.63, 23.90) and the lowest is in the Tigray region 4.81% (95% CI 2.75, 6.87). Besides, the proportion of mortality among children with low CD4 count and hemoglobin level was 2.42 (AOR = 2.42, 95% CI 1.65, 3.56) and 3.24 (AOR = 3.24, 95% CI 1.51, 6.93) times higher compared to their counterparts, respectively.

Conclusion

The proportion of mortality among children on ART was high in Ethiopia. Those children who had low CD4 cell count and low hemoglobin levels at baseline need special attention, treatment, and care.

Trial registration

The protocol of this systematic review and meta-analysis has been registered in PROSPERO with the registration number CRD42018113077.

Pneumococcal vaccination for HIV-infected individuals in Singapore

Susceptibility to infections with pneumococcal bacteria ( Streptococcus pneumoniae) is substantially higher among human immunodeficiency virus (HIV)-infected individuals, and accounts for a significant burden of morbidity and healthcare costs. Pneumococcal vaccination is recommended in most countries for HIV-infected adults. Current policy in Singapore and Australia recommends the use of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) as a booster dose following the use of 13-valent pneumococcal conjugate vaccine (PCV13). Despite this, adherence to this policy has been suboptimal in Singapore. This may be related to the fact that PPSV23 has not been shown to have any impact on pneumococcal carriage (the necessary prerequisite for disease development). PPSV23 has also been associated with immune hyporesponsiveness, raising concerns over the use of this vaccine globally and, in particular, in high-risk populations. The lack of data from studies comparing PCV13 and PPSV23 has also contributed to the suboptimal uptake of pneumococcal vaccines by healthcare professionals for HIV-infected individuals. This review article discusses the key issues and importance of rigorous pneumococcal vaccination programmes for HIV-infected individuals. Current recommendations for pneumococcal vaccination of HIV-infected individuals in Singapore should be adopted more readily to reduce the burden of pneumococcal disease in this high-risk group.

Pneumococcal conjugate vaccine in HIV-infected and HIV-exposed, uninfected children

INTRODUCTION

Incidence of invasive pneumococcal disease (IPD) among HIV-infected children is 20-40 fold greater compared to HIV-uninfected children, including among HIV-infected children on antiretroviral therapy (ART). Also, HIV-exposed, uninfected children have 2.7-fold greater risk of IPD compared to HIV-unexposed children. Areas covered: We reviewed studies identified on Pubmed database with the terms 'PCV' and 'HIV'; studies involving adults only were excluded. Expert commentary: While ART and pneumococcal conjugate vaccines (PCV) have reduced IPD morbidity and mortality in HIV-infected children, ART-naïve and immunosuppressed children have inferior immunogenicity to most PCV serotypes; highlighting the need for concomitant use of ART with PCV. Furthermore, studies to determine optimal PCV dosing schedules, timing and number of doses, are urgently required to ensure sustained vaccine efficacy in HIV-infected children.

Evolving role of 13-valent pneumococcal conjugate vaccine in clinical practice

Since the introduction of 7-valent pneumococcal conjugate vaccine (PCV7), PCVs with extended coverage have become available, and there is emerging global evidence that these vaccines, in particular PCV13, have further reduced rates of invasive pneumococcal disease compared with PCV7. The present article aims to address emerging topics related to PCV13 use in routine clinical practice; specifically: (1) the potential role of high-valent PCVs in reducing pneumococcal disease burden; (2) the impact of PCVs on nasopharyngeal carriage and how this may contribute to reductions in otitis media and pneumonia, as well as the prevalence of resistant pneumococcal strains; (3) new PCV13 indications and (4) importance of schedule adherence for PCV in the prevention of cases of vaccine serotype-specific invasive pneumococcal disease. The beneficial effects of PCVs in protecting individuals from a wide spectrum of pneumococcal diseases can be increased by improving the vaccine coverage and adhering to the recommended vaccination schedules. There is increasing evidence that PCV13 has reduced much of the post-PCV7 burden of pneumococcal diseases in the pediatric community, including reducing pneumococcal colonization and the incidence of invasive pneumococcal disease and mucosal diseases. This has also led to a reduction in antibiotic-resistant pneumococcal diseases. The role of PCV13 in clinical practice is evolving, with PCV13 now available for children and adolescents between the ages of 6 weeks and 17 years, thus ensuring that children in all age groups can be protected against vaccine-serotype pneumococcal diseases. Continued surveillance is warranted to monitor the impact of PCV13 on disease burden.

Risk factors for death and severe sequelae in Malawian children with bacterial meningitis, 1997-2010

BACKGROUND

Acute bacterial meningitis (ABM) causes significant death and disability in children worldwide, with HIV recognized as an established risk factor for infection and negative outcomes. However, additional major risk factors for death and disability in pediatric ABM remain unclear.

METHODS

We conducted a retrospective analysis of case data from 3 departmental studies of ABM involving 1784 children <15 years old who attended Queen Elizabeth Central Hospital in Blantyre, Malawi during 1997 to 2010. Univariate and multivariate logistic regression models were used to estimate the effects of HIV seropositivity, impaired consciousness and causative organism on death and severe sequelae.

RESULTS

Impaired consciousness or coma at the time of admission was strongly associated with death (coma: odds ratio [OR] = 14.4, 95% confidence interval [CI]: 9.42, 22.1) and severe sequelae (Coma: OR = 3.27, 95% CI: 2.02, 5.29) in multivariate logistic regression models. HIV seropositivity was significantly associated with increased odds of death (OR = 1.65, 95% CI: 1.20, 2.26) but not with developing severe sequelae (OR = 0.88, 95% CI: 0.56, 1.38). After adjustment, infection with Salmonella spp. was associated with increased odds of death (OR = 2.11, 95% CI: 1.06, 4.08) and pneumococcal meningitis was associated with increased odds of severe sequelae (OR = 1.84, 95% CI: 1.03, 3.29).

CONCLUSIONS

Impaired consciousness and HIV infection increased the odds of death from ABM in Malawian children. Use of pneumococcal conjugate vaccine could greatly reduce the burden of ABM in Malawi.

Impact of cotrimoxazole on carriage and antibiotic resistance of Streptococcus pneumoniae and Haemophilus influenzae in HIV-infected children in Zambia

This is a substudy of a larger randomized controlled trial on HIV-infected Zambian children, which revealed that cotrimoxazole prophylaxis reduced morbidity and mortality despite a background of high cotrimoxazole resistance. The impact of cotrimoxazole on the carriage and antibiotic resistance of Streptococcus pneumoniae and Haemophilus influenzae as major causes of childhood mortality in HIV-infected children was investigated since these are unclear. Representative nasopharyngeal swabs were taken prior to randomization for 181 of 534 children (92 on cotrimoxazole and 89 on placebo). Bacterial identification and antibiotic susceptibility were performed by routine methods. Due to reduced mortality, prophylactic cotrimoxazole increased the median time from randomization to the last specimen from 48 to 56 months (P = 0.001). The carriage of H. influenzae was unaltered by cotrimoxazole. Carriage of S. pneumoniae increased slightly in both arms but was not statistically significant in the placebo arm. In S. pneumoniae switching between carriage and no carriage in consecutive pairs of samples was unaffected by cotrimoxazole (P = 0.18) with a suggestion that the probability of remaining carriage free was lower (P = 0.10). In H. influenzae cotrimoxazole decreased switching from carriage to no carriage (P = 0.02). Cotrimoxazole resistance levels were higher in postbaseline samples in the cotrimoxazole arm than in the placebo arm (S. pneumoniae, P < 0.0001; H. influenzae, P = 0.005). Cotrimoxazole decreased switching from cotrimoxazole resistance to cotrimoxazole sensitivity in S. pneumoniae (P = 0.002) and reduced the chance of H. influenzae remaining cotrimoxazole sensitive (P = 0.05). No associations were observed between the percentage of CD4 (CD4%), the change in CD4% from baseline, child age at date of specimen, child gender, or sampling month with carriage of either pathogen.

Hospitalizations for invasive pneumococcal disease among human immunodeficiency virus-1 infected children, adolescents and young adults in the United States in the era of highly active antiretroviral therapy and the conjugate pneumococcal vaccine

We describe hospitalization trends of invasive pneumococcal disease (IPD) among human immunodeficiency virus-infected individuals <25 years of age since the introduction of highly active antiretroviral therapy (HAART) and the 7-valent pneumococcal conjugate vaccine (PCV7) in the United States, using the Nationwide Inpatient Sample. We estimated national trends of IPD hospitalizations during 3 periods: 1994 to 1995 (pre-HAART and pre-PCV7 era); 1998 to 1999 (HAART and pre-PCV7 era); and 2004 to 2005 (HAART and early PCV7 era). The number of IPD hospitalizations among human immunodeficiency virus-infected children and youth <25 years in the United States declined by 78.7% between 1994/1995 and 2004/2005 (P = 0.03). This decrease was more pronounced among younger children.

The evidence for using conjugate vaccines to protect HIV-infected children against pneumococcal disease

Pneumococcal conjugate vaccines (PCVs) are a potentially useful complement to existing treatment strategies in HIV-infected children, for whom pneumococcal infections are common and serious. This Review summarises available data on the burden of pneumococcal disease and the safety and efficacy of PCVs in HIV-infected children. The data demonstrate that children with HIV have significantly increased risk of pneumococcal disease compared with uninfected children; the serotypes included in currently licensed or near-licensure conjugate vaccines include most serotypes that cause invasive pneumococcal disease (IPD) in HIV-infected children and adults; PCVs provide substantial protection against IPD and clinical pneumonia when given to HIV-infected infants; and HIV-infected adults gain an indirect benefit when children in the community are vaccinated. PCV should be considered as an important intervention for improving the lives of HIV-infected children.

Pneumococcal conjugate vaccines—a European perspective

Streptococcus pneumoniae is a leading cause of bacterial pneumonia, meningitis, and acute otitis media in children and adults worldwide. In the age group of < 2 years the incidence of invasive pneumococcal disease ranges from approximately 14 cases per 100,000 in Germany and the Netherlands and more than 90 per 100,000 children in Spain. The vulnerability of children to S. pneumoniae can also be demonstrated by the high rate of sequelae (> 20% in Germany) and the high mortality (7.5%) in pneumococcal meningitis. Furthermore, antibiotic resistance of S. pneumoniae is increasing in Europe, particularly in France, Spain, and Eastern European countries, whereas Germany and Northern Europe are only marginally affected. A 7-valent pneumococcal conjugate vaccine (7vPCV) that was shown to be highly efficacious in preventing invasive pneumococcal disease in infants in the USA was licensed in Europe in 2001. It is expected that broad usage of the vaccine would reduce the incidence of invasive pneumococcal disease and the levels of pneumococcal resistance significantly. Important questions have been raised regarding the effectiveness of this vaccine in high-risk populations, serotype replacement, the efficacy of this vaccine in otitis media, and the co-administration of the new vaccine with other standard childhood vaccines used in various European countries. France and Spain currently have the most-wide ranging guidelines recommending pneumococcal vaccination for children. Overall, the development of pneumococcal conjugate vaccines is a significant step in the control of pneumococcal disease in children in Europe. Further progress in pneumococcal vaccine development can be expected from conjugate vaccines including more than seven serotypes (9-valent, 11-valent).

Immunogenicity of 23-valent pneumococcal polysaccharide vaccine in children with human immunodeficiency virus undergoing highly active antiretroviral therapy

BACKGROUND

The 23-valent pneumococcal polysaccharide vaccine (23PSV) has been recommended for children infected with human immunodeficiency virus (HIV); however, the efficacy of this vaccination in HIV-infected children undergoing highly active antiretroviral therapy (HAART) has not been studied.

OBJECTIVE

To study the immunogenicity and immunologic protection of 23PSV in HIV-infected children after stable HAART.

METHODS

Serotype-specific IgG antibodies to 12 pneumococcal capsular polysaccharides were analyzed before and after 23PSV vaccination in 41 HIV-infected children undergoing HAART and compared with 95 HIV-negative control children. Seropositivity, clinical protection, and additional clinical protection from 23PSV were calculated based on serotype specific IgG antibody levels and on the known incidence of these serotypes for causing invasive disease.

RESULTS

Children with HIV infection undergoing HAART developed a significant increase in specific IgG levels to Streptococcus pneumoniae after 23PSV vaccination (0.95 vs 1.84 micro/gmL, P < .001). The HIV-infected children with CD4+ cell counts of 25% or higher at the time of vaccination developed a higher additional clinical protection gain from 23PSV vaccination than did children with a lower percentage of CD4+ cells.

CONCLUSIONS

HIV-infected children undergoing stable HAART develop a significant immunologic response to 23PSV, especially those with higher T-cell counts and lower viral loads at the time of vaccination.

The future of pneumococcal conjugate vaccines for prevention of pneumococcal diseases in infants and children

Seven-valent pneumococcal conjugate vaccine (PCV7) was licensed in February 2000. In June 2000, the Advisory Committee on Immunization Practices and the American Academy of Pediatrics recommended the universal administration of pneumococcal conjugate vaccine for all children 23 months of age and younger and for children 24 to 59 months of age who are at high risk for serious pneumococcal disease. Since then, >23 million doses have been administered in the United States. Postlicensure surveillance of invasive pneumococcal disease (IPD) in the United States from the Active Bacterial Core Surveillance program at the Centers for Disease Control and Prevention and the Northern California Kaiser Permanente Vaccine Study Center has reported a decline in IPD and in pneumococcal disease incidence as a result of vaccine serotypes, respectively. During this period, issues critical to the long-term success of PCV7 have become more relevant: Will PCV7 be as effective in groups of children who are at high risk for IPD as in healthy children? Will nonvaccine types replace vaccine serotypes in the nasopharynx and in disease? Why are the results of the clinical trials different for IPD and for acute otitis media? How many doses of PCV7 and what concentrations of antibody are necessary for protection? Will universal administration of PCV7 to children younger than 2 years reduce antimicrobial drug resistance and alter prescribing patterns of physicians for febrile infants? Have there been unanticipated adverse events or benefits observed? The purpose of this report is to review the current data available to address these questions and to identify gaps that will require additional knowledge to determine the ultimate value of pneumococcal conjugate vaccines in reducing the burden of pneumococcal disease in infants and children.

Pneumococcal vaccination of children

Streptococcus pneumoniae is the most frequent cause of invasive bacterial infection in children younger than 2 years of age, reaching a peak incidence at 6 to 12 months of age. Pneumococci also cause many cases of pneumonia, sinusitis, and otitis media. Incidence rates of invasive infection in children with sickle cell disease, acquired or congenital splenectomy, or human immunodeficiency virus infection are 20- to 100-fold higher than are those of healthy children during the first 5 years of life. Other healthy children, such as those of American Indian, Native Alaskan, or African American descent, also have high rates of invasive infection, and those children enrolled in out-of-home care may have modestly increased risks. Pneumococcal polysaccharide polyvalent vaccines have been available for more than 2 decades but are limited in their usefulness for children because of their inability to induce protective antibody responses in children younger than 2 years of age and lack of immunologic memory. In contrast, pneumococcal protein conjugate vaccines induce presumptive protective responses in infants younger than 6 months, and immunologic memory further enhances responses after booster doses are given. Currently, a single heptavalent pneumococcal protein conjugate vaccine is licensed for use in the United States and is recommended for routine administration to all children, beginning at 2 months of age. It also is recommended for children between 24 and 59 months of age who are at high risk of acquiring invasive disease.

Acquired disorders of phagocyte function complicating medical and surgical illnesses

There is evidence that acquired dysfunction of neutrophils, monocytes, or macrophages is an important cause of infection in patients with diabetes mellitus, renal or hepatic failure, alcoholism, autoimmune diseases, influenza or human immunodeficiency virus infection, burns, and trauma. Distinguishable mechanisms of acquired phagocyte dysfunction include inhibitory effects of metabolic disturbances (e.g., hyperglycemia, uremia), chemical toxins (e.g., ethanol), viral proteins on phagocyte activation, and pathologic activation of phagocytes in the circulation (e.g., after hemodialysis, burns, or cardiopulmonary bypass). Although the burden of morbidity and mortality resulting from acquired phagocyte dysfunction appears to be vast, research in this area has been hampered by the complexity of the underlying illnesses and by limitations of laboratory assays and clinical study methodology. Given the advent of improved assays of phagocyte functions and treatments that can enhance these functions, there is a pressing need for more prospective studies of acquired phagocyte dysfunction.

Failure of the conjugate pneumococcal vaccine to prevent recurrent bacteremia in a child with human immunodeficiency virus disease

Patients with advanced HIV disease have a poor response to some immunizations. A case is presented of a Class C1 HIV-infected child who suffered three episodes of Streptococcus pneumoniae serotype 6B bacteremia despite having received the heptavalent conjugate and 23-valent polysaccharide pneumococcal vaccines. Clinicians should expect some vaccine failures with the heptavalent conjugate vaccine in children with advanced HIV disease.

Management of fever without source in infants and children

Twenty percent of febrile children have fever without an apparent source of infection after history and physical examination. Of these, a small proportion may have an occult bacterial infection, including bacteremia, urinary tract infection (UTI), occult pneumonia, or, rarely, early bacterial meningitis. Febrile infants and young children have, by tradition, been arbitrarily assigned to different management strategies by age group: neonates (birth to 28 days), young infants (29 to 90 days), and older infants and young children (3 to 36 months). Infants younger than 3 months are often managed by using low-risk criteria, such as the Rochester Criteria or Philadelphia Criteria. The purpose of these criteria is to reduce the number of infants hospitalized unnecessarily and to identify infants who may be managed as outpatients by using clinical and laboratory criteria. In children with fever without source (FWS), occult UTIs occur in 3% to 4% of boys younger than 1 year and 8% to 9% of girls younger than 2 years of age. Most UTIs in boys occur in those who are uncircumcised. Occult pneumococcal bacteremia occurs in approximately 3% of children younger than 3 years with FWS with a temperature of 39.0 degrees C (102.2 degrees F) or greater and in approximately 10% of children with FWS with a temperature of 39.5 degrees C (103.1 degrees F) or greater and a WBC count of 15, 000/mm(3) or greater. The risk of a child with occult pneumococcal bacteremia later having meningitis is approximately 3%. The new conjugate pneumococcal vaccine (7 serogroups) has an efficacy of 90% for reducing invasive infections of Streptococcus pneumoniae. The widespread use of this vaccine will make the use of WBC counts and blood cultures and empiric antibiotic treatment of children with FWS who have received this vaccine obsolete.

American Academy of Pediatrics. Committee on Infectious Diseases. Technical report: prevention of pneumococcal infections, including the use of pneumococcal conjugate and polysaccharide vaccines and antibiotic prophylaxis

Pneumococcal infections are the most common invasive bacterial infections in children in the United States. The incidence of invasive pneumococcal infections peaks in children younger than 2 years, reaching rates of 228/100,000 in children 6 to 12 months old. Children with functional or anatomic asplenia (including sickle cell disease [SCD]) and children with human immunodeficiency virus infection have pneumococcal infection rates 20- to 100-fold higher than those of healthy children during the first 5 years of life. Others at high risk of pneumococcal infections include children with congenital immunodeficiency; chronic cardiopulmonary disease; children receiving immunosuppressive chemotherapy; children with immunosuppressive neoplastic diseases; children with chronic renal insufficiency, including nephrotic syndrome; children with diabetes; and children with cerebrospinal fluid leaks. Children of Native American (American Indian and Alaska Native) or African American descent also have higher rates of invasive pneumococcal disease. Outbreaks of pneumococcal infection have occurred with increased frequency in children attending out-of-home care. Among these children, nasopharyngeal colonization rates of 60% have been observed, along with pneumococci resistant to multiple antibiotics. The administration of antibiotics to children involved in outbreaks of pneumococcal disease has had an inconsistent effect on nasopharyngeal carriage. In contrast, continuous penicillin prophylaxis in children younger than 5 years with SCD has been successful in reducing rates of pneumococcal disease by 84%. Pneumococcal polysaccharide vaccines have been recommended since 1985 for children older than 2 years who are at high risk of invasive disease, but these vaccines were not recommended for younger children and infants because of poor antibody response before 2 years of age. In contrast, pneumococcal conjugate vaccines (Prevnar) induce proposed protective antibody responses (>.15 microg/mL) in >90% of infants after 3 doses given at 2, 4, and 6 months of age. After priming doses, significant booster responses (ie, immunologic memory) are apparent when additional doses are given at 12 to 15 months of age. In efficacy trials, infant immunization with Prevnar decreased invasive infections by >93% and consolidative pneumonia by 73%, and it was associated with a 7% decrease in otitis media and a 20% decrease in tympanostomy tube placement. Adverse events after the administration of Prevnar have been limited to areas of local swelling or erythema of 1 to 2 cm and some increase in the incidence of postimmunization fever when it is given with other childhood vaccines. Based on data in phase 3 efficacy and safety trials, the US Food and Drug Administration has provided an indication for the use of Prevnar in children younger than 24 months.

Colonization by Streptococcus penumoniae in human immunodeficiency virus-infected children

OBJECTIVE

Children with HIV infection are particularly susceptible to invasive pneumococcal disease, yet the effect of HIV infection and its medical management on colonization and resistance to antibiotics are poorly described. To provide a basis for medical practice, we determined the prevalence of nasopharyngeal colonization and antibiotic resistance of Streptococcus pneumoniae in children with HIV infection.

METHODS

Cross-sectional prevalence sample of children attending the pediatric HIV and pulmonary clinics to examine nasopharyngeal colonization with S. pneumoniae and antibiotic resistance to beta-lactams and trimethoprim-sulfamethoxazole (T/S). Subjects were matched by age and date of clinic visit.

RESULTS

The colonization rate with S. pneumoniae of HIV-infected and -indeterminate children was equal to that of controls (20% vs. 19%). HIV infection, CDC staging or receipt of oral antibiotic therapy did not affect colonization. Isolates from HIV-infected and -indeterminate children were less likely to be penicillin-resistant than those from controls (18% vs. 50%). There was no difference in pneumococcal resistance to T/S among isolates from subjects and controls, despite 72% T/S use in the HIV clinic.

CONCLUSION

Colonization with S. pneumoniae in HIV disease is no different from that of comparable children. The high incidence of pneumococcal disease and prophylaxis with T/S are not related to nasopharyngeal colonization. Antibiotic prophylaxis of HIV-infected children does not necessarily lead to increased resistance of S. pneumoniae.

Pneumococcal bacteremia during a decade in children in Soweto, South Africa

OBJECTIVES

To monitor for a decade the incidence and the clinical and microbiologic characteristics of pneumococcal bacteremia in children in Soweto and to assess the influence of HIV infection on any changes.

METHODS

Case records of children with pneumococcal bacteremia at Chris Hani Baragwanath Hospital from July, 1986, to June, 1987 (1986/ 1987), and from July, 1996, to June, 1997 (1996/ 1997), were retrospectively reviewed.

RESULTS

There were 194 episodes, 62 in 19861 1987 and 132 in 1996/1997. The minimum annual incidence for children younger than 5 years of age increased from 61 per 100000 (179 per 100000 for those <12 months old) in 1986/1987 to 130 per 100000 (349 per 100000 for those <12 months old) in 1996/1997. Sixty-seven (60%) of 111 patients tested in 1996/1997 were HIV-seropositive; none were tested in 1986/1987. The HIV-infected compared with HIV-noninfected were more likely to be malnourished (61% vs. 36%, P = 0.02), less likely to have other underlying disease (12% vs. 50%, P = 0.00001) and more frequently used antibiotics recently (69% vs. 43%, P = 0.008). Penicillin-nonsusceptible isolates were found in 22 (35%) patients in 1986/1987 and 52 (39%) in 1996/1997. There was no significant change in antimicrobial susceptibility during the decade or by HIV serostatus.

CONCLUSIONS

Children in Soweto had a high incidence of pneumococcal bacteremia which doubled during the decade mainly as a result of the impact of the HIV epidemic. There has been no significant change in antimicrobial susceptibility for the decade.

Opportunistic infections and other clinical manifestations of HIV disease in children

As the decade draws to a close, physicians can be cautiously optimistic about the prevention and treatment of opportunistic infections in children with HIV disease. As more children receive therapy with powerful antiretroviral regimens, fewer are likely to be at risk for opportunistic pathogens. The widespread use of protease inhibitor combination therapies has already resulted in a dramatic decrease in morbidity and mortality in the population of HIV-infected adults. The same effect has been seen at pediatric care centers throughout the United States. Clinicians caring for HIV-infected children are now considering the safety of discontinuing prophylactic therapies for children with sustained immunologic improvement on antiretroviral therapy. For children who remain at risk, prophylactic regimens for PCP and MAC have been shown to decrease the risk for these infections. Preventive regimens for several other opportunistic infections are also available. The understanding of the pathogenesis of HIV and many of the opportunistic pathogens has led to the development of a variety of efficacious therapies for these infections. Despite these advances, physicians can anticipate that HIV-infected children will continue to develop opportunistic infections and other related complications. Some children fail to respond to antiretroviral therapies, whereas others are unable to tolerate the complex medication regimens. Prophylactic therapies are not 100% protective and, despite improved treatments, few opportunistic infections are cured. Most require lifelong maintenance therapy in the absence of immune reconstitution. Drug interactions, complex dosing schedules, adverse side effects, and high costs further limit the efficacy of these therapies. The prophylaxis, diagnosis, and treatment of opportunistic infections are likely to remain integral components of HIV care for the near and distant future.

Bacteremic pneumococcal pneumonia in HIV-seropositive and HIV-seronegative adults

STUDY OBJECTIVES

To compare the demographic, clinical, laboratory, and microbiological data, and the hospital course and outcome of HIV-seropositive and HIV-seronegative adults with bacteremic pneumococcal pneumonia.

DESIGN

Retrospective observation study conducted over a 2-year period.

SETTING

Academic teaching hospital attached to the University of the Witwatersrand, Johannesburg, South Africa.

PATIENTS

Consecutive patients with bacteremic pneumococcal pneumonia were identified on the basis of positive blood culture results.

INTERVENTIONS

All available demographic, clinical, routine laboratory, radiographic, and microbiological data were recorded retrospectively for each of the patients, and the combined data for the HIV-seropositive patients were compared with those of the HIV-seronegative patients.

MEASUREMENT AND RESULTS

A total of 112 patients (31 HIV-seropositive and 81 HIV-seronegative patients) were entered into the study. The HIV-seropositive patients were significantly younger than the HIV-seronegative patients (32.8 vs 39.6 years old) and had lower admission hemoglobin (11.8 vs 13.4 g/dL), WBC count (10.3 vs 14.3 x 10(9)/L), serum albumin (31 vs 36 g/L), sodium (129 vs 132 mmol/L), and potassium (3.0 vs 3.5 mmol/L), respectively. Although the HIV-seropositive patients appeared to have more multilobar pulmonary consolidation on the chest radiograph than the HIV-seronegative patients (60% vs 34%), this did not quite reach statistical significance. In addition, the HIV-seropositive patients had significantly more infections (48.4% vs 20.8%) with pneumococcal serogroups/serotypes (serogroups 6, 19, 23, and serotype 14) that are found more commonly in children, and they also had more penicillin-resistant isolates (13% vs 2.5%) than the HIV-seronegative patients, respectively. Similarly, it was noted that when these data were analyzed according to gender (irrespective of HIV status), women had significantly more infections than men (47% vs 21%) with serogroups/serotypes that are usually found in children, more penicillin-resistant isolates (15% vs 1%), and more co-trimoxazole-resistant isolates (21% vs 5%), respectively. There were no differences noted in any of the other parameters, including initial APACHE (acute physiology and chronic health evaluation) II score, PaO2/fraction of inspired oxygen ratio, duration of temperature, duration of IV therapy, duration of hospitalization, complications, and outcome, when comparing HIV-seropositive and HIV-seronegative patients. Two patients in each group died.

CONCLUSIONS

The clinical features of bacteremic pneumococcal pneumonia are similar in HIV-seropositive and HIV-seronegative patients. Although differences are noted in various laboratory and microbiological parameters, they do not appear to have an impact on outcome.

The impact of HIV on Streptococcus pneumoniae bacteraemia in a South African population

OBJECTIVES

To determine the impact of HIV infection on Streptococcus pneumoniae bacteraemia in adults and children by analysing the prevalence and clinical features of such diseases and determining the prevalent serotypes/serogroups and susceptibility patterns of isolates.

DESIGN

Patients were identified prospectively from January to October 1996.

SETTING

Chris Hani Baragwanath Hospital, Soweto, a tertiary referral hospital treating adults and children, in an urban district near Johannesburg, South Africa.

PATIENTS AND METHODS

All patients with S. pneumoniae isolated from blood culture by the Microbiology Department, Chris Hani Baragwanath Hospital were studied. Clinical and microbiological features were recorded.

RESULTS

A total of 178 patients with S. pneumoniae were investigated as part of the study; 49 were aged < 13 years. HIV seroinfection was present in 25 (51%) children and 58 (45%) adults. The incidence of S. pneumoniae bacteraemia was 36.9-fold increased in HIV-seropositive children and 8.2-fold increased in HIV-seropositive adults compared with HIV-seronegative individuals. Both adult and paediatric HIV-seropositive patients with S. pneumoniae bacteraemia were significantly younger than HIV-seronegative patients. Pneumonia was a significantly more common presentation in HIV-seropositive children, otherwise the spectrum of disease and outcome were similar in HIV-seronegative and positive groups. Serotype 1 S. pneumoniae isolates were significantly less common in HIV-infected individuals (both adults and children). Resistance to penicillin was increased in S. pneumoniae isolates from HIV-infected patients (significant in adults). Patients with penicillin-resistant isolates did not have a poorer outcome. The potential coverage of serotypes/serogroups included in the proposed nine-valent conjugate pneumococcal vaccine was 88% in HIV-seronegative children and 83% in HIV-seropositive children. The potential coverage of the currently available 23-valent pneumococcal vaccine for adults was 98.2 and 100)% for HIV-infected and HIV-uninfected adults, respectively.

CONCLUSION

The burden of bacteraemia due to S. pneumoniae in HIV-seropositive individuals admitted to our hospital is considerable. Differences in the S. pneumoniae serotypes/serogroups in HIV-infected patients have been demonstrated with resultant differences in antibiotic susceptibility patterns. Excellent potential for vaccine coverage was demonstrated for both HIV-seronegative and HIV-seropositive individuals. Further studies are necessary to test the clinical efficacy of pneumococcal vaccination of HIV-seropositive adults and children as a potential preventative measure against this prevalent disease.

The clinical impact of resistance in the management of pneumococcal disease

The prevalence of drug-resistant Streptococcus pneumoniae (DRSP) has increased worldwide. Although unfavorable outcomes in meningitis due to DRSP have been well-described, the clinical impact of DRSP on other manifestations of pneumococcal infection warrants further study. Empiric combination vancomycin and extended-spectrum cephalosporin (cefotaxime or ceftriaxone) therapy is indicated for the following clinical indications: purulent meningitis, life-threatening pneumonia, and suspected sepsis in patients predisposed to invasive pneumococcal disease, for example, sickle cell disease, HIV infection, and nephrotic syndrome. In addition to clinical management issues, other implications of the emergence of DRSP include identification of resistant strains, local and national surveillance, and prevention. Preventive measures include judicious antibiotic use, appropriate use of the currently available 23-valent pneumococcal vaccine, and development and implementation of a protein-conjugate vaccine.

Fc gammaRIIa polymorphism in human immunodeficiency virus-infected children with invasive pneumococcal disease

Invasive pneumococcal disease (IPD) occurs frequently in HIV-infected children and adults. Defects in complement function, opsonic capsular antibodies, and Fc receptor antibody-mediated phagocytosis could contribute to impaired host defense against Streptococcus pneumoniae. The objective of this study was to define the distribution of the three Fc gammaRIIa genotypes in HIV+ children, including those with IPD. Forty-eight HIV+ Hispanic children, including eight with IPD, followed at Bronx-Lebanon Hospital Center, Bronx, New York, nine HIV+ adults with IPD, and 56 HIV- Hispanic control subjects were studied. The children and adults were identified retrospectively except for one child who developed IPD during the study. Fc gammaRIIa genotypes were determined by PCR amplification of the Fc gammaRIIa locus from genomic DNA samples and hybridization of the PCR products with allele-specific oligonucleotides. Naturally occurring serum antibodies reactive with four pneumococcal polysaccharide serotypes were determined by ELISA in seven of eight children with IPD. There were no statistical differences in Fc gammaRIIa genotypes between HIV+ children with and without IPD, HIV+ adults with IPD, or HIV- Hispanics. The predominant IgG subclass of pneumococcal polysaccharide binding antibodies in the seven HIV+ children with IPD studied was IgG1. The distribution of Fc gammaRIIa genotypes in HIV+ children with and without IPD is similar to that of the normal Hispanic population. The prospect of passive immunotherapy with specific anticapsular antibodies might be a promising alternative for the treatment and/or prevention of IPD in HIV+ children and other immunodeficient groups.