Immune reconstitution syndrome from nontuberculous mycobacterial infection after initiation of antiretroviral therapy in children with HIV infection

What Came First: Malnutrition or Severe Disease?

A 20-year-old female with depression presented to the emergency department with chronic weight loss, weakness, fatigue, hair loss, rash, palpitations, and 2 weeks of cough. Initial history revealed that she had disordered eating habits with dietary restriction, experienced a 50-pound unintentional weight loss over 2 years despite reported adherence to nutritional supplementation, and had a normal gastrointestinal workup. On examination, she was markedly cachectic with a BMI of 10.3kg/m2 and hypotensive (84/69 mmHg). Her cardiovascular examination revealed a regular rate and rhythm without a murmur. Her breath sounds were diminished in the upper lobes bilaterally. A skin examination showed diffuse hair loss, skin breakdown, and peeling with a tender, erythematous, papular rash over the bilateral ankles, and nonpitting edema. A chest radiograph showed a right upper lobe opacity and lucent lesions in the left proximal humerus. A focused assessment with sonography for trauma examination showed a large pericardial effusion. Chest computed tomography revealed a right upper lobe opacity with an associated cavitation. Though she began improving with rifampin, isoniazid, pyrazinamide, ethambutol, levofloxacin, azithromycin, and nutritional rehabilitation, her clinical course was complicated by an acute worsening nearly 1 month into her hospitalization with persistent high fevers, worsening cough, development of a murmur, and worsening consolidation on chest computed tomography. Adolescent Medicine, Infectious Diseases, Gastroenterology, and Allergy and Immunology were consulted to guide the diagnostic evaluation and management of this patient's complex clinical course.

Case Report: Nontuberculous mycobacterial infections in children with complete DiGeorge anomaly

Children with complete DiGeorge anomaly (cDGA) have congenital athymia, resulting in severe T cell immunodeficiency and susceptibility to a broad range of infections. We report the clinical course, immunologic phenotypes, treatment, and outcomes of three cases of disseminated nontuberculous mycobacterial infections (NTM) in patients with cDGA who underwent cultured thymus tissue implantation (CTTI). Two patients were diagnosed with Mycobacterium avium complex (MAC) and one patient with Mycobacterium kansasii. All three patients required protracted therapy with multiple antimycobacterial agents. One patient, who was treated with steroids due to concern for immune reconstitution inflammatory syndrome (IRIS), died due to MAC infection. Two patients have completed therapy and are alive and well. T cell counts and cultured thymus tissue biopsies demonstrated good thymic function and thymopoiesis despite NTM infection. Based on our experience with these three patients, we recommend that providers strongly consider macrolide prophylaxis upon diagnosis of cDGA. We obtain mycobacterial blood cultures when cDGA patients have fevers without a localizing source. In cDGA patients with disseminated NTM, treatment should consist of at least two antimycobacterial medications and be provided in close consultation with an infectious diseases subspecialist. Therapy should be continued until T cell reconstitution is achieved.

Surgical implications of HIV infection

According to the joint United Nations Programme on HIV/AIDS (UNAIDS), 37.7 million adults and children worldwide were estimated to be living with HIV or acquired immune deficiency syndrome (AIDS) at the end of 2020 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. Most reside in low- and middle-income countries, with approximately 67% in sub-Saharan Africa (SSA). At the end of 2020, the total number of children less than 15 years of age living with HIV infection was 2.6 million, of whom 2.3 million (88%) were living in SSA. Aggressive interventions have reduced the annual number of incident (new) HIV infections among children to around 150,000 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. However, paediatric HIV infection remains a pandemic affecting children predominantly in SSA but is also seen in Asia and sporadically elsewhere particularly in areas of civil strife such as is currently the case in Ukraine [War in Ukraine. (2022). https://www.unaids.org/en/War-Ukraine-special . Accessed Apr 2022]. New HIV infections among children declined by more than half (54%) from 2010 to 2020, due mainly to the increased provision of antiretroviral therapy to pregnant and breastfeeding women living with HIV [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. These programmes include early identification of HIV infection in pregnant or breastfeeding women through routine HIV testing, provision of antiretroviral therapy (ART) to all HIV-infected women who are pregnant or breastfeeding, provision of antiretroviral prophylaxis to their newborn infants during the first 6-12 weeks of life, delivery by elective Caesarean section when indicated, promotion of exclusive breastfeeding, early infancy screening for HIV infection, and initiation of ART in infants with HIV infection. HIV-infected children may require surgery either as an emergency to deal with a life-threatening incidental condition unrelated to HIV infection or for a complication of the disease such as tuberculosis or an aggressive soft tissue infection like necrotising fasciitis. Non-emergency surgical procedures may be required to assist in the diagnosis of an HIV-related condition or to correct a routine surgical problem electively. Surgical conditions associated with HIV infection are described under categories of soft tissue or organ-specific infections requiring drainage or debridement; gastrointestinal tract disease and complications; infections in the perineal area; malignancies and HIV-associated vasculitis. Although surgical outcomes are less favourable in HIV-infected children, pre-operative treatment of coinfections, administration of cotrimoxazole prophylaxis, nutritional support and antiretroviral therapy, together with peri-operative antibiotic prophylaxis have resulted in excellent short-term outcomes [World Health Organization. Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection: Recommendations for a public health approach, June 201 http://www.apps.who.int/iris/bitstream/10665/85321/1/9789241505727_eng.pdf?ua=1 ; World Health Organization Guideline on when to start antiretroviral therapy and on pre-exposure prophylaxis for HIV, September 2015. http://www.apps.who.int/iris/bitstream/10665/186275/1/9789241509565_eng.pdf?ua=1;Eley et al. in BMC Infect Dis 2:3, 2002;Karpelowsky et al. in Pediatr Surg Int 28:1007-1014, 2012;].

An Exclusively Skewed Distribution of Pediatric Immune Reconstitution Inflammatory Syndrome Toward the Female Sex Is Associated With Advanced Acquired Immune Deficiency Syndrome

In human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) patients with very low CD4 cell counts, there is a temporal relationship between administration of antiretroviral therapy (ART) and an increased inflammatory response state known as the immune reconstitution inflammatory syndrome (IRIS). The predominant clinical presentation of IRIS is an infectious disease that can be life-threatening. IRIS-related infectious events are distributed similarly between adult males and females, albeit a few studies have shown a skewing toward the male sex in pediatric IRIS. Here, we assessed sex-specific differences in the causes and extent of IRIS infectious events in HIV-infected pediatric patients on ART. We carried out a prospective clinical analysis (from 2000 to 2018) of IRIS-related infectious events after ART in a cohort of 82 Brazilian children and adolescents infected with HIV-1 through mother-to-child transmission as well as a comprehensive cross-referencing with public records on IRIS-related infectious causes in pediatric HIV/AIDS. Twelve events fulfilling the criteria of IRIS occurred exclusively in 11 females in our cohort. The median age at IRIS events was 3.6 years. The infectious causes included Mycobacterium bovis, varicella-zoster virus, molluscum contagiosum virus, human papillomavirus, cytomegalovirus, and Mycobacterium tuberculosis. In one female, there was regional bacillus Calmette-Guérin dissemination and cytomegalovirus esophagitis. There was complete health recovery after 10 IRIS events without the use of corticosteroids or ART interruption. One case of IRIS-associated miliary tuberculosis was fatal. The biological female sex was a significant risk factor for IRIS events (odds ratio: 23.67; 95% confidence interval 95%: 1.341-417.7; P = 0.0016 and P < 0.01 by the multivariable analysis). We observed an effect of the advanced HIV/AIDS variable in IRIS females as compared with non-IRIS females (mean CD4⁺ T cell percentage 13.36 vs. 18.63%; P = 0.0489 and P < 0.05 by the multivariable analysis), underpinning the exclusively skewed distribution toward the female sex of this cohort. Moreover, the IRIS females in our cohort had higher mean CD4⁺ T cell percentages before (13.36%) and after IRIS (26.56%) than those of the IRIS females (before IRIS, 4.978%; after IRIS, 13.81%) in previous studies conducted worldwide. The exclusively skewed distribution of pediatric IRIS toward the female sex in the cohort was not linked to preferential X-chromosome inactivation rates. We concluded that the exclusively skewed distribution of pediatric IRIS toward females is associated with more advanced AIDS.

Urgent versus post-stabilisation antiretroviral treatment in hospitalised HIV-infected children in Kenya (PUSH): a randomised controlled trial

BACKGROUND

Urgent antiretroviral therapy (ART) among hospitalised HIV-infected children might accelerate recovery or worsen outcomes associated with immune reconstitution. We aimed to compare urgent versus post-stabilisation ART among hospitalised HIV-infected children in Kenya.

METHODS

In this unmasked randomised controlled trial, we randomly assigned (1:1) HIV-infected, ART-naive children aged 0-12 years who were eligible for treatment to receive ART within 48 h (urgent group) or in 7-14 days (post-stabilisation group) at four hospitals in Kenya (two in Nairobi and two in western Kenya). We excluded children with suspected or confirmed CNS infection. A statistician not involved in study procedures did block randomisation with variable block sizes generated using STATA version 12. We followed children for 6 months for primary outcomes: mortality, drug toxicity, and immune reconstitution inflammatory syndrome (IRIS). We did all analyses in a modified intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT02063880.

FINDINGS

We began enrolment on April 24, 2013, and completed follow-up on Nov 17, 2015. We enrolled 191 (76%) of 250 hospitalised HIV-infected children. Of these, 183 children were randomly assigned: 90 to urgent ART and 93 to post-stabilisation ART. 181 (99%) of 183 children were included in the modified intention-to-treat analysis. Median age was 1·9 years (IQR 0·8-4·8). Baseline sociodemographic, clinical, and virological characteristics did not differ between groups except median CD4 cell percentage, which was lower in the urgent group (13% [IQR 9-18] vs 17% [IQR 9-24]; p=0·052). Of 181 admission diagnoses, 118 (65%) were pneumonia, 58 (32%) malnutrition, and 27 (15%) suspected tuberculosis. Median time to ART was 1 day (IQR 1-1) in the urgent group and 8 days (IQR 7-11) in the post-stabilisation group. Overall, mortality risk at 6 months was 61 per 100 person-years. Mortality risk did not differ by group (70 per 100 person-years in the urgent group vs 54 per 100 person-years in the post-stabilisation group; hazard ratio [HR] 1·26, 95% CI 0·67-2·37) p=0.47, even after adjusting for baseline CD4 cell percentage (adjusted HR 1·30, 95% CI 0·69-2·45; p=0·41). The incidence of IRIS, and drug toxicity was not significantly different between trial arms. There were no differences between treatment groups in the proportion of grade 3 or 4 adverse events (34 [38%] of 90 children in the urgent group vs 40 [44%] of 91 children in the post-stabilisation group; p=0·40) or the proportion of any change in ART regimen (five [7%] vs six [8%]; p=0·79). We discontinued randomisation at interim review when the futility boundary was crossed.

INTERPRETATION

Early mortality risk was extremely high among hospitalised HIV-infected children. Urgent ART did not improve survival.

FUNDING

National Institute of Child Health and Human Development, National Institutes of Health, USA.

The chest X-ray features of chronic respiratory disease in HIV-infected children--a review

Several features of human immunodeficiency virus (HIV) infection contribute to the development of chronic respiratory disease in children. These include the frequency and severity of acute chest infections, as well as the increased risk of pulmonary tuberculosis, aspiration, cardiovascular disease, lymphocytic interstitial pneumonitis or pulmonary neoplasia. The chest radiograph (CXR) remains the most accessible investigation for respiratory disease and plays an important role in the baseline assessment and follow-up. This review focuses on the CXR abnormalities of HIV-related chronic respiratory disease in children. The most commonly documented chronic CXR abnormalities are homogeneous opacification and pulmonary nodules, with pulmonary tuberculosis and lymphocytic interstitial pneumonitis the leading respective causes. Deficiencies in radiographic reporting methodology and relative paucity of radiographic data contribute to current limitations in knowledge and understanding of this field. The review highlights the need for standardised terminology and systematic reporting methodology in future studies. Prospective research on the natural history of lymphocytic interstitial pneumonitis, response to anti-tuberculous therapy, the impact of anti-retroviral therapy and HIV-associated bronchiectasis are needed.

Mycobacterium haemophilum bone and joint infection in HIV/AIDS: case report and literature review

We report a case of disseminated Mycobacterium haemophilum osteomyelitis in a patient with advanced HIV infection, who later developed recurrent immune reconstitution inflammatory syndrome after commencement of antiretroviral therapy. We review previous reports of M. haemophilum bone and joint infection associated with HIV infection and describe the management of M. haemophilum-associated immune reconstitution inflammatory syndrome, including the role of surgery as an adjunctive treatment modality and the potential drug interactions between antiretroviral and antimycobacterial agents.

Characterization of Proinflammatory Responses and Innate Signaling Activation in Macrophages Infected with Mycobacterium scrofulaceum

Mycobacterium scrofulaceum is an environmental and slow-growing atypical mycobacterium. Emerging evidence suggests that M. scrofulaceum infection is associated with cervical lymphadenitis in children and pulmonary or systemic infections in immunocompromised adults. However, the nature of host innate immune responses to M. scrofulaceum remains unclear. In this study, we examined the innate immune responses in murine bone marrow-derived macrophages (BMDMs) infected with different M. scrofulaceum strains including ATCC type strains and two clinically isolated strains (rough and smooth types). All three strains resulted in the production of proinflammatory cytokines in BMDMs mediated through toll-like receptor-2 and the adaptor MyD88. Activation of MAPKs (extracellular signal-regulated kinase 1/2, and p38, and c-Jun N-terminal kinase) and nuclear receptor (NF)-κB together with intracellular reactive oxygen species generation were required for the expression of proinflammatory cytokines in BMDMs. In addition, the rough morphotypes of M. scrofulaceum clinical strains induced higher levels of proinflammatory cytokines, MAPK and NF-κB activation, and ROS production than other strains. When mice were infected with different M. scrofulaceum strains, those infected with the rough strain showed the greatest hepatosplenomegaly, granulomatous lesions, and immune cell infiltration in the lungs. Notably, the bacterial load was higher in mice infected with rough colonies than in mice infected with ATCC or smooth strains. Collectively, these data indicate that rough M. scrofulaceum induces higher inflammatory responses and virulence than ATCC or smooth strains.

[Infections due to Mycobacterium simiae]

Mycobacterium simiae is a slow-growing photochromogenic environmental mycobacterium, first described in 1965. Rarely associated with human infections, possibly due to its limited pathogenicity, it mainly produces lung infection in immunocompetent elderly patients with underlying lung disease, and in disseminated infections in immunosuppressed young patients with AIDS. A microbiological culture is needed to confirm the clinical suspicion, and genetic sequencing techniques are essential to correctly identify the species. Treating M. simiae infections is complicated, owing to the multiple resistance to tuberculous drugs and the lack of correlation between in vitro susceptibility data and in vivo response. Proper treatment is yet to be defined, but must include clarithromycin combined with other antimicrobials such as moxifloxacin and cotrimoxazole. It is possible that M. simiae infections are undiagnosed.

Incidence, spectrum and outcome of immune reconstitution syndrome in HIV-infected children after initiation of antiretroviral therapy

BACKGROUND

Immune reconstitution syndrome (IRS) is a relatively common complication in HIV-infected adults starting combination antiretroviral therapy (cART). Data on IRS in HIV-infected children remain limited and are largely restricted to resource-limited settings. This study investigated the incidence, spectrum and outcome of IRS in a pediatric cohort in the United Kingdom.

METHODS

Retrospective analysis of clinical events during the first 12 months after initiation of cART in 135 treatment-naïve, HIV-infected children in the United Kingdom over a 5-year period. Demographic and laboratory data were provided by the Collaborative HIV Paediatric Study.

RESULTS

The median age at cART initiation was 6.6 years (interquartile range: 2.3-10.2). The median CD4 lymphocyte percentage (CD4%) at baseline was 15% (median CD4 lymphocyte count: 390 cells/μL). Eight patients (5.9%) developed IRS (incidence: 5.7/100 person years). The IRS events comprised: Bacillus Calmette-Guerin-related complications (local ulceration/lymphadenitis; n = 4), pulmonary tuberculosis (n = 1), Mycobacterium avium intracellulare infection (n = 1), combined tuberculosis/Mycobacterium avium intracellulare infection (n = 1) and cutaneous herpes simplex (n = 1). The mortality was significantly higher in children with IRS than in those without (P < 0.0001). The only statistically significant risk factor for IRS identified was increment in CD4 count at 12 months after starting cART (P = 0.03).

CONCLUSIONS

The incidence of IRS was significantly lower than previously reported from resource-limited settings, likely reflecting less profound immunodeficiency at cART initiation and fewer coexisting opportunistic infections in our cohort. However, IRS events were associated with considerable morbidity and mortality. Therefore, preventive strategies that can reduce the risk of IRS in children need to be identified.

Incidence of opportunistic illness before and after initiation of highly active antiretroviral therapy in children

BACKGROUND

Little is known about immune reconstitution inflammatory syndrome in children in the United States.

METHODS

LEGACY is a longitudinal cohort study of HIV-infected participants 0-24 years at enrollment during 2005 to 2007 from 22 US clinics. For this analysis, we included participants with complete medical record abstraction from birth or time of HIV diagnosis through 2006. Opportunistic illness (OI) included AIDS-defining conditions and selected HIV-related diagnoses. We calculated the incidence (#/100 patient-years) of OI diagnosed in the months pre- and postinitiation of the first highly active antiretroviral therapy (HAART) regimen which was followed by ≥1 log reduction in HIV viral load. We defined OI as immune reconstitution inflammatory syndrome if an OI incidence increased after HAART initiation. "Responders" were defined as experiencing ≥1 log decline in viral load within 6 months after HAART initiation.

RESULTS

Among 575 patients with complete chart abstraction, 524 received HAART. Of these 524 patients, 343 were responders, 181 were nonresponders and 86 experienced OI. Responders accounted for 98 of 124 (79%) of OI. Pre-HAART and post-HAART OI incidences were 43.7 and 24.4 (P = 0.003), respectively, among responders and 15.9 and 9.1 (P = 0.2), respectively, among nonresponders. Overall, OI incidences among responders and nonresponders were 33.8 and 12.3, respectively (P = 0.002). Responders were more likely than nonresponders to experience herpes simplex and herpes zoster before HAART initiation (all, P < 0.002).

CONCLUSIONS

The lack of immune reconstitution inflammatory syndrome in participants initiating HAART may be due to low overall OI rates. The unexpectedly higher OI prevalence comprised mainly of herpes simplex and zoster, before HAART initiation among responders, may have motivated them to better adhere to HAART.

Paradoxical Mycobacterium tuberculosis meningitis immune reconstitution inflammatory syndrome in an HIV-infected child

Immune reconstitution inflammatory syndrome occurs in a subset of HIV-infected individuals as the immune system recovers secondary to antiretroviral therapy. An exaggerated and uncontrolled inflammatory response to antigens of viable or nonviable organisms is characteristic, with clinical deterioration despite improvement in laboratory indicators. We describe a fatal case of Mycobacterium tuberculosis meningitis immune reconstitution inflammatory syndrome in an HIV-infected child and review the literature.

Mesenterial, omental, and peritoneal disorders in antiretroviral-treated HIV/AIDS patients: spectrum of cross-sectional imaging findings

In the era of highly active antiretroviral therapy, radiologists are increasingly confronted with a progressively aging HIV-infected population with improved immune function and survival, in whom a wide spectrum of infectious and neoplastic opportunistic disorders may be encountered. Furthermore, HIV / AIDS patients commonly have unspecific symptoms and physical signs, multicentric or coexisting diseases, so that diagnostic imaging studies are crucial to correctly identify and stage HIV-related abnormalities. Currently, volumetric multidetector CT (MDCT) provides comprehensive assessment and confident post-treatment follow-up of opportunistic abnormalities involving the mesentery, omentum, and peritoneum. In this pictorial essay, the cross-sectional imaging appearances of opportunistic disorders involving the mesentery, peritoneum, or both compartments in HIV / AIDS patients are reviewed, with emphasis on those MDCT findings that may be helpful for differential diagnosis along with knowledge of the degree of immune suppression as measured by the CD4 lymphocyte count. Familiarity with the varied spectrum of HIV-related opportunistic disorders encountered in antiretroviral - treated patients and their imaging appearances should allow radiologists to improve their confidence in the characterization of abnormal findings observed on abdominal cross-sectional imaging studies.

Causes of first hospitalization among 1121 HIV-infected children: comparison of the pre-Pneumocystis jiroveci pneumonia prophylaxis, pre-antiretroviral therapy and antiretroviral therapy periods

This study identified causes of first hospitalization among perinatally acquired HIV-infected children at Chiang Mai University Hospital between 1989 and 2009. Data were stratified into three seven-year time periods: pre-Pneumocystis jiroveci pneumonia (PJP) prophylaxis, pre-antiretroviral therapy (ART) and ART period. Over the 21-year study period, 1121 children were hospitalized. The mean age at admission was 2.7 years and had become older over time. Of the 1121 hospitalization causes, 50.6% were AIDS-defining illnesses (ADIs), 48.1% were non-AIDS-defining illnesses (NADIs) and 1.3% were related to immune reconstitution syndrome. Types of ADIs changed over time: PJP and recurrent Salmonella septicaemia decreased, while mycobacterial infection and systemic fungal infection increased. For NADIs, bacterial infections, viral infections and gastrointestinal problems decreased, but haematological problems increased in the third period. Decline in the number of hospitalizations and mortality rate, increase in the mean age of hospitalized children, change in the distribution of specific illnesses and appearance of immune reconstitution syndrome were observed in the ART period.

Surgical implications of human immunodeficiency virus infections

Pediatric HIV (human immunodeficiency virus) is a pandemic predominantly in sub-Saharan Africa. Approximately 2.2 million children aged less than 15 years are infected with HIV, representing almost 95% of the total number of children globally infected with HIV. Therefore, increasing numbers of HIVi or -exposed but uninfected children can be expected to require a surgical procedure to assist in the diagnosis of an HIV/acquired immune deficiency syndrome-related complication, to address a life-threatening complication of the disease, or for routine surgery encountered in HIV-unexposed children. HIVi children may present with both conditions unique to HIV infection and surgical conditions routine in pediatric surgical practice. HIV exposure confers an increased risk of complications and mortality for all children after surgery, whether they are HIV infected or not. This risk of complications is higher in the HIVi group of patients. These findings seem to be independent of whether patients undergo an elective or emergency procedure, but the risk of an adverse outcome is higher for a major procedure. Surgical implications of HIV infection are comprehensively reviewed in this article.

BCG-itis in two antiretroviral-treated HIV-infected infants

Although vaccination with Bacille Calmette-Guérin (BCG) is considered safe, adverse regional (BCG-itis) and disseminated (BCG-osis) diseases preferentially occur in the immunocompromised host. The infection with human immunodeficiency virus (HIV) by mother-to-child transmission leads to impaired cellular immune responses, a situation that poses a great challenge regarding the universal use of BCG vaccine. World Health Organization recommends that children who are known to be HIV-infected, even if asymptomatic, should no longer be immunized with BCG. Many of the complications of BCG vaccination occur in severely immunosuppressed HIV-infected children and are related to late institution of antiretroviral and antimycobacterial therapy. We report two cases of BCG-itis in HIV-infected infants, who fulfilled clinical criteria of immune reconstitution inflammatory syndrome: axillary adenitis, one with suppuration, and both temporally associated with precocious restoration of immunity elicited by the use of antiretroviral therapy. Isoniazid (10 mg/kg/day) was offered until regression of adenopathies, and lesions were not handled.

Risk factors for immune reconstitution inflammatory syndrome under combination antiretroviral therapy can be aetiology-specific

In order to discriminate general from aetiology-specific risk factors for immune reconstitution inflammatory syndrome (IRIS), we followed up, during six months, 99 patients with advanced HIV infection commencing antiretroviral therapy (ART) without active opportunistic infections or evident inflammation. IRIS predictors were determined by univariate analysis using clinical data from 76 ART-responding patients either completing follow-up or developing IRIS, and by multivariate analysis of inflammation, disease progression and nutrition status variables. We identified 23 primary IRIS events (30.3%). Univariate predictors for all IRIS events were higher platelet counts and lower CD4/CD8 ratio, whereas subclinical inflammation was the multivariate predictor. Platelets, alkaline phosphatase levels and %CD8 T-cells in univariate analysis also predicted mycobacteria-associated IRIS independently, remaining elevated during follow-up. Herpesvirus IRIS was predicted by platelets and inflammation. Indicators of advanced HIV disease and subclinical inflammation jointly predict IRIS, and some are specific of the underlying microbial aetiology, possibly explaining previous reports.

Inflammatory BCG adenitis associated with immune reconstitution following allogeneic haematopoietic stem cell transplant in infancy

We describe four cases of a localized, granulomatous reaction to BCG including ipsilateral painful, suppurative lymphadenopathy associated with donor immune reconstitution following allogeneic haematopoietic stem cell transplant performed in infancy and preceded by uneventful, routine BCG immunisation. The management of the inflammatory disease in these cases with surgery, antimycobacterial chemotherapy and steroids, is discussed.

Immune reconstitution disease associated with mycobacterial infections

PURPOSE OF REVIEW

We review immune reconstitution disease associated with mycobacterial infections in patients receiving antiretroviral treatment. We draw particular attention to data relevant to resource-limited settings and focus predominantly on publications over the past year.

RECENT FINDINGS

Worldwide mycobacteria are the most important group of pathogens associated with immune reconstitution disease. In cohorts of patients with tuberculosis in high-income countries, up to one-third develop immune reconstitution disease compared with only 8-13% in current reports from resource-limited settings. We speculate on potential explanations for this difference. While most cases of tuberculosis immune reconstitution disease are self-limiting, deaths have been reported in South African and Thai cohorts. We discuss how risk and outcomes of tuberculosis immune reconstitution disease represent key variables regarding the optimum time to initiate antiretroviral treatment in tuberculosis patients. A new conceptual framework has been proposed regarding 'unmasking' of tuberculosis during antiretroviral treatment. Increasing numbers of cases of leprosy immune reconstitution disease and Bacillus Calmette-Guérin immune reconstitution disease have also been reported, mainly from resource-limited settings. Immune reconstitution disease associated with a variety of mycobacteria (tuberculous and nontuberculous) was common in a cohort of Thai children.

SUMMARY

Immune reconstitution disease associated with a range of mycobacteria constitutes a challenge to delivery of antiretroviral treatment worldwide. Data concerning the pathogenesis and management of all forms of mycobacterial immune reconstitution disease are lacking.

Pediatric HIV immune reconstitution inflammatory syndrome

PURPOSE OF REVIEW

Little is known regarding HIV immune reconstitution inflammatory syndrome in children. As the antiretroviral therapy roll out has gathered pace since 2004 in resource-limited settings, pediatric immune reconstitution inflammatory syndrome has emerged as a clinical challenge.

RECENT FINDINGS

The incidence of immune reconstitution inflammatory syndrome appears to be between 10 and 20%. The commonest causes are mostly mycobacterial, including tuberculosis, atypical mycobacteria and bacillus Calmette-Guérin related. In many pediatric cohorts, however, a marked early mortality within the first 90 days of antiretroviral therapy occurs. This mortality is poorly understood, and the contribution of immune reconstitution inflammatory syndrome to this mortality is unknown.

SUMMARY

Children after starting antiretroviral therapy may have paradoxical worsening of previously treated opportunistic infections. Due to the differences, however, in children's immunology with vertical HIV transmission, children are probably at greater risk of unmasking occult, subclinical infections during immune reconstitution.

Guidelines for the Prevention and Treatment of Opportunistic Infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics

This report updates and combines into one document earlier versions of guidelines for preventing and treating opportunistic infections (OIs) among HIV-exposed and HIV-infected children, last published in 2002 and 2004, respectively. These guidelines are intended for use by clinicians and other health-care workers providing medical care for HIV-exposed and HIV-infected children in the United States. The guidelines discuss opportunistic pathogens that occur in the United States and one that might be acquired during international travel (i.e., malaria). Topic areas covered for each OI include a brief description of the epidemiology, clinical presentation, and diagnosis of the OI in children; prevention of exposure; prevention of disease by chemoprophylaxis and/or vaccination; discontinuation of primary prophylaxis after immune reconstitution; treatment of disease; monitoring for adverse effects during treatment; management of treatment failure; prevention of disease recurrence; and discontinuation of secondary prophylaxis after immune reconstitution. A separate document about preventing and treating of OIs among HIV-infected adults and postpubertal adolescents (Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents) was prepared by a working group of adult HIV and infectious disease specialists. The guidelines were developed by a panel of specialists in pediatric HIV infection and infectious diseases (the Pediatric Opportunistic Infections Working Group) from the U.S. government and academic institutions. For each OI, a pediatric specialist with content-matter expertise reviewed the literature for new information since the last guidelines were published; they then proposed revised recommendations at a meeting at the National Institutes of Health (NIH) in June 2007. After these presentations and discussions, the guidelines underwent further revision, with review and approval by the Working Group, and final endorsement by NIH, CDC, the HIV Medicine Association (HIVMA) of the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Disease Society (PIDS), and the American Academy of Pediatrics (AAP). The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of the evidence supporting the recommendation so readers can ascertain how best to apply the recommendations in their practice environments. An important mode of acquisition of OIs, as well as HIV infection among children, is from their infected mother; HIV-infected women coinfected with opportunistic pathogens might be more likely than women without HIV infection to transmit these infections to their infants. In addition, HIV-infected women or HIV-infected family members coinfected with certain opportunistic pathogens might be more likely to transmit these infections horizontally to their children, resulting in increased likelihood of primary acquisition of such infections in the young child. Therefore, infections with opportunistic pathogens might affect not just HIV-infected infants but also HIV-exposed but uninfected infants who become infected by the pathogen because of transmission from HIV-infected mothers or family members with coinfections. These guidelines for treating OIs in children therefore consider treatment of infections among all children, both HIV-infected and uninfected, born to HIV-infected women. Additionally, HIV infection is increasingly seen among adolescents with perinatal infection now surviving into their teens and among youth with behaviorally acquired HIV infection. Although guidelines for postpubertal adolescents can be found in the adult OI guidelines, drug pharmacokinetics and response to treatment may differ for younger prepubertal or pubertal adolescents. Therefore, these guidelines also apply to treatment of HIV-infected youth who have not yet completed pubertal development. Major changes in the guidelines include 1) greater emphasis on the importance of antiretroviral therapy for preventing and treating OIs, especially those OIs for which no specific therapy exists; 2) information about the diagnosis and management of immune reconstitution inflammatory syndromes; 3) information about managing antiretroviral therapy in children with OIs, including potential drug--drug interactions; 4) new guidance on diagnosing of HIV infection and presumptively excluding HIV infection in infants that affect the need for initiation of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PCP) in neonates; 5) updated immunization recommendations for HIV-exposed and HIV-infected children, including hepatitis A, human papillomavirus, meningococcal, and rotavirus vaccines; 6) addition of sections on aspergillosis; bartonella; human herpes virus-6, -7, and -8; malaria; and progressive multifocal leukodystrophy (PML); and 7) new recommendations on discontinuation of OI prophylaxis after immune reconstitution in children. The report includes six tables pertinent to preventing and treating OIs in children and two figures describing immunization recommendations for children aged 0--6 years and 7--18 years. Because treatment of OIs is an evolving science, and availability of new agents or clinical data on existing agents might change therapeutic options and preferences, these recommendations will be periodically updated and will be available at http://AIDSInfo.nih.gov.

Reduced rate of adverse reactions to the BCG vaccine in children exposed to the vertical transmission of HIV infection and in HIV-infected children from an endemic setting in Brazil

We report on the adverse reactions to the Bacillus Calmette-Guérin (BCG) vaccine in BCG-vaccinated children. We examined children exposed to the vertical transmission of human immunodeficiency virus (HIV) (n = 141), who participated in a prevention program of vertical transmission, and HIV-infected children (n = 66) in a setting endemic for HIV and tuberculosis (TB) in Brazil from August 2000 to February 2008. No cases of disseminated BCG disease occurred in either group of children. While no cases of regional BCG disease were noted in exposed/uninfected children, the rate of regional BCG disease in HIV-infected children was 4.5% (3/66); the three events occurred in <1-year-old children (3/17; 17.6%). One case was associated with severe immunodepression before highly active antiretroviral therapy (HAART). Two cases were manifestations of immune reconstitution inflammatory syndrome (IRIS). Among the HIV-infected children, the accrued benefits of potentially preventing severe TB outweighed the risks associated with the use of the BCG vaccine.

Cutaneous Mycobacterium avium complex infection as a manifestation of the immune reconstitution syndrome in a human immunodeficiency virus-infected child

We report a 13-year-old boy with human immunodeficiency virus infection who developed cutaneous Mycobacterium avium complex infection 2 months after commencing highly active antiretroviral therapy. The case illustrates that cutaneous Mycobacterium avium complex may present as a manifestation of the immune reconstitution syndrome in human immunodeficiency virus-infected children.

New concepts in childhood tuberculosis

PURPOSE OF REVIEW

Childhood tuberculosis has long been neglected in international tuberculosis control efforts. There are, however, many opportunities to prevent childhood tuberculosis that are not being fully employed.

RECENT FINDINGS

Several papers have been published to emphasize the unique nature of childhood tuberculosis and improve tuberculosis control in children. Treatment regimens have been improved and refined. Clinical and radiographic methods have been standardized. While new diagnostic tests are greatly needed, it is also apparent that any new tests--such as the interferon release assays--will need to be studied specifically in infants and children or there is a risk they may be misapplied. The areas of greatest need for research and clinical utility remain better diagnostic tests for tuberculosis infection and disease; shorter and more effective regimens for treating tuberculosis infection; better integration of children into standard tuberculosis control practices; a better understanding of the interaction of human immunodeficiency virus infection and tuberculosis in children; detection and treatment of drug-resistant tuberculosis in children; and a more effective vaccine.

SUMMARY

True progress will require a rethinking of basic tuberculosis control with a commitment to address problems specific to childhood tuberculosis.

Mycobacterium simiae complex infection in an immunocompetent child

Nontuberculous mycobacteria are ubiquitous in the environment but rarely infect immunocompetent patients. We describe a pediatric case of Mycobacterium simiae complex lymphadenitis in an immunocompetent child and review the natural history, clinical manifestations, diagnosis, and current management of the disease.

Mycobacterium simiae cervical lymphadenitis

Mycobacterium simiae, a multidrug-resistant, opportunistic acid-fast bacillus, usually causes infection in immunocompromised hosts. We describe a previously healthy child with M. simiae necrotizing granulomatous cervical lymphadenitis. Cure was achieved with excision of the affected nodes and adjunctive antimicrobial therapy.