[Myelin Oligodendrozyten Glycoprotein Antikörper-assoziierte bilaterale Neuritis nervi optici bei einem 5-jährigen Mädchen]

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A neomorphic variant in SP7 alters sequence specificity and causes a high-turnover bone disorder

SP7/Osterix is a transcription factor critical for osteoblast maturation and bone formation. Homozygous loss-of-function mutations in SP7 cause osteogenesis imperfecta type XII, but neomorphic (gain-of-new-function) mutations of SP7 have not been reported in humans. Here we describe a de novo dominant neomorphic missense variant (c.926 C > G:p.S309W) in SP7 in a patient with craniosynostosis, cranial hyperostosis, and long bone fragility. Histomorphometry shows increased osteoblasts but decreased bone mineralization. Mice with the corresponding variant also show a complex skeletal phenotype distinct from that of Sp7-null mice. The mutation alters the binding specificity of SP7 from AT-rich motifs to a GC-consensus sequence (typical of other SP family members) and produces an aberrant gene expression profile, including increased expression of Col1a1 and endogenous Sp7, but decreased expression of genes involved in matrix mineralization. Our study identifies a pathogenic mechanism in which a mutation in a transcription factor shifts DNA binding specificity and provides important in vivo evidence that the affinity of SP7 for AT-rich motifs, unique among SP proteins, is critical for normal osteoblast differentiation.

Osteoarticular Infections in Pediatric Hospitals in Europe: A Prospective Cohort Study From the EUCLIDS Consortium

BACKGROUND

Pediatric osteoarticular infections (POAIs) are serious diseases requiring early diagnosis and treatment.

METHODS

In this prospective multicenter cohort study, children with POAIs were selected from the European Union Childhood Life-threatening Infectious Diseases Study (EUCLIDS) database to analyze their demographic, clinical, and microbiological data.

RESULTS

A cohort of 380 patients with POAIs, 203 with osteomyelitis (OM), 158 with septic arthritis (SA), and 19 with both OM and SA, was analyzed. Thirty-five patients were admitted to the Pediatric Intensive Care Unit; out of these, six suffered from shock, one needed an amputation of the right foot and of four left toes, and two had skin transplantation. According to the Pediatric Overall Performance Score, 36 (10.5%) showed a mild overall disability, 3 (0.8%) a moderate, and 1 (0.2%) a severe overall disability at discharge. A causative organism was detected in 65% (247/380) of patients. Staphylococcus aureus (S. aureus) was identified in 57.1% (141/247) of microbiological confirmed cases, including 1 (0.7%) methicillin-resistant S. aureus (MRSA) and 6 (4.2%) Panton-Valentine leukocidin (PVL)-producing S. aureus, followed by Group A Streptococcus (18.2%) and Kingella kingae (8.9%). K. kingae and PVL production in S. aureus were less frequently reported than expected from the literature.

CONCLUSION

POAIs are associated with a substantial morbidity in European children, with S. aureus being the major detected pathogen. In one-third of patients, no causative organism is identified. Our observations show an urgent need for the development of a vaccine against S. aureus and for the development of new microbiologic diagnostic guidelines for POAIs in European pediatric hospitals.

Granulozytendefekte

Hereditäre Störungen der Granulozyten betreffen das angeborene Immunsystem („innate immunity“). Sie lassen sich in Erkrankungen mit quantitativer Reduktion und funktionellen Störungen der Granulozyten/Phagozyten einteilen. Sie können ferner isoliert oder als Begleitsymptom weiterer Störungen auftreten. Pathogenetisch sind Mutationen in so unterschiedlichen Molekülen wie Enzymen, Transkriptionsfaktoren, Adhäsionsproteinen und Strukturproteinen ursächlich beteiligt. Der folgende Übersichtsartikel stellt die Krankheitsbilder schwere kongenitale Neutropenie, zyklische Neutropenie, Shwachman-Diamond-Syndrom, Glykogenose Ib, Chediak-Higashi-Syndrom, Dyskeratosis congenita, Knorpel-Haar-Hypoplasie, Leukozytenadhäsionsdefekte I-III, ß-Actin-Defizienz, RAC-2-Defizienz, spezifischer Granula-Defekt, Glukose-6-Phosphat-Dehydrogenase sowie chronische Granulomatose vor.

[Guideline for antiretroviral therapy of HIV-infected children and adolescents]

The HIV-infection in adults or children and adolescent differs substantially. Differences include the mode of infection, viral dynamics facing a developing immune system and the clinical course of the infection. In addition to the virological, immunological and epidemiological aspects the psychosocial situation is also very different. The above aspects and the decreased number of antiretroviral substances underline the need for specific guidelines for HIV-therapy in children and adolescents. The German Pediatric Working group AIDS (PAAD) has formulated this guideline in 2011 based on new study results, changes in international recommendations and newly available drugs.

Terminally differentiated CD8 cells in HIV-infected children: HIV-GAG/POL specificity and IFN-γ production

BACKGROUND

CD8 cells are key to antiviral immunity and can be divided by phenotype into early (CD28+ CD27+), intermediate (CD28-CD27+) and terminally differentiated subsets (CD28- CD27-). Despite effective HAART there is an unexplained expansion of CD8+CD28-CD27-T cells in HIV-infected children. The cytokine production and specificity of this terminally differentiated CD8 T cell subset in chronic virus infection is unclear. PATIENTS, METHODS & RESULTS: In a cohort of 26 HIV-infected children the cytokine production of terminally differentiated CD8 cells was analyzed by intracellular staining and FACS analysis and was compared to children with chronic hepatitis B infection and to healthy children. The specificity of CD8 subsets was analyzed by staining with Gag/Pol tetramers in a cohort of 13 patients. We show that an increased production of interferon-γ in terminally and early/intermediate differentiated CD8 cell subsets after stimulation is specific for HIV-infection. The expanded population of terminally differentiated CD8+CD28-CD27- T cells does include HIV Gag/Pol specific T cells in adults but not in children.

CONCLUSION

The expansion of terminally differentiated CD8 cells might be important for immunomodulation but in children it does not appear to play a role in HIV Gag and Pol specific immunity.

Successful long-term correction of autosomal recessive hyper-IgE syndrome due to DOCK8 deficiency by hematopoietic stem cell transplantation

Autosomal dominant hyper-IgE syndrome (AD-HIES), characterised by eczema, increased susceptibility to skin and lung infections, elevated IgE and skeletal abnormalities is associated with heterozygous STAT3 mutations. The autosomal recessive variant (AR-HIES) has similar immunological findings but mainly lacks extraimmune manifestations. Several AR-HIES patients have recently been shown to harbour mutations in the gene for dedicator of cytokinesis 8 (DOCK8). Here, we present the long-term outcome of a girl having received a hematopoietic stem cell graft for an at that time genetically undefined combined immunodeficiency associated with severe eczema, multiple food allergies, excessively elevated serum IgE levels and eosinophilia. She was recently found to carry a homozygous nonsense mutation in the DOCK8 gene. HSCT resulted in complete immunological correction, even though mixed donor chimerism occurred. Clinically, the outcome was characterised by disappearance of skin manifestations and severe infections, improvement of pulmonary function and constant decline of IgE levels. Outcome in untransplanted DOCK8 deficient patients is poor because of frequent life-threatening infections, CNS bleeding and infarction, and increased susceptibility to malignancy. This argues for early curative therapeutic approaches, supported by this report of successful long-term outcome after HSCT.

PENTA 2009 guidelines for the use of antiretroviral therapy in paediatric HIV-1 infection

PENTA Guidelines aim to provide practical recommendations for treating children with HIV infection in Europe. Changes to guidance since 2004 have been informed by new evidence and by expectations of better outcomes following the ongoing success of antiretroviral therapy (ART). Participation in PENTA trials of simplifying treatment is encouraged. The main changes are in the following sections: 'When to start ART': Treatment is recommended for all infants, and at higher CD4 cell counts and percentages in older children, in line with changes to adult guidelines. The number of age bands has been reduced to simplify and harmonize with other paediatric guidelines. Greater emphasis is placed on CD4 cell count in children over 5 years, and guidance is provided where CD4% and CD4 criteria differ. 'What to start with': A three-drug regimen of two nucleoside reverse transcriptase inhibitors (NRTIs) with either a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a boosted protease inhibitor (PI) remains the first choice combination. Lamivudine and abacavir are the NRTI backbone of choice for most children, based on long-term follow-up in the PENTA 5 trial. Stavudine is no longer recommended. Whether to start with an NNRTI or PI remains unclear, but PENPACT 1 trial results in 2009 may help to inform this. All PIs should be ritonavir boosted. Recommendations on use of resistance testing, therapeutic drug monitoring and HLA testing draw from data in adults and from European paediatric cohort studies. Recently updated US and WHO paediatric guidelines provide more detailed review of the evidence base. Differences between guidelines are highlighted and explained.

Addison's disease and severe encephalopathy in an infant with HIV infection

AIM

To discuss the overlapping clinical spectrum of encephalopathy due to Addison's disease and HIV infection.

PATIENT

We report a 2.5-year-old boy from Uzbekistan with recurrent episodes of encephalopathy and seizures, triggered by infection or vaccinations, in whom adrenal insufficiency and infection with HIV and HCV was diagnosed. Presumably, Addisonian crises prompted hypovolemic shock and blood transfusions, which were responsible for horizontal HIV infection. The combination of adrenal insufficiency and HIV infection eventually led to progressive severe encephalopathy. Despite highly active antiretroviral therapy (which led to substantial reduction of blood viral load), the neurological condition did not improve.

DISCUSSION

The interactions of Addison's disease and HIV in the pathogenesis of encephalopathy are discussed.

Clinical score for nonbacterial osteitis in children and adults

OBJECTIVE

To accurately differentiate nonbacterial osteitis (NBO) from other bone lesions by applying a clinical score through the use of validated diagnostic criteria.

METHODS

A retrospective study was conducted to assess data on patients from a pediatric clinic and an orthopedic tertiary care clinic, using administrative International Classification of Diseases codes as well as laboratory and department records from 1996 to 2006. Two hundred twenty-four patients older than age 3 years who had either NBO (n = 102), proven bacterial osteomyelitis (n = 22), malignant bone tumors (n = 48), or benign bone tumors (n = 52) were identified by chart review. Univariate logistic regression was used to determine associations of single risk factors with a diagnosis of NBO, and multivariable logistic regression was used to assess simultaneous risk factor associations with NBO.

RESULTS

NBO was best predicted by a normal blood cell count (odds ratio [OR] 81.5), symmetric bone lesions (OR 30.0), lesions with marginal sclerosis (OR 26.8), normal body temperature (OR 20.3) a vertebral, clavicular, or sternal location of lesions (OR 13.9), presence of >1 radiologically proven lesion (OR 10.9), and C-reactive protein level > or =1 mg/dl (OR 6.9). The clinical score for a diagnosis of NBO based on these predictors ranged from 0 to 63. A score for NBO of > or =39 had a positive predictive value of 97% and a sensitivity of 68%.

CONCLUSION

The proposed scoring system helps to facilitate the diagnostic process in patients with suspected NBO. Use of this system might spare unnecessary invasive diagnostic and therapeutic procedures.

Common variable immunodeficiency disorders in children: delayed diagnosis despite typical clinical presentation

OBJECTIVE

To characterize common variable immunodeficiency disorder (CVID) in childhood.

STUDY DESIGN

We retrospectively investigated clinical findings in 32 children with primary CVID by questionnaire and file review.

RESULTS

Clinical presentation included recurrent or chronic respiratory tract infections (88%), sinusitis (78%), otitis media (78%), and intestinal tract infections (34%), mainly with encapsulated bacteria. Meningitis was found in 25%, sepsis in 16%, and pyelonephritis in 16% of patients. Poliomyelitis after vaccination occurred in 2 patients and opportunistic infections occasionally. Allergic disorders were present in 38%, and autoimmune disease in 31% of patients. Eighty percent of the patients underwent surgical procedures because of recurrent infections. Growth retardation was seen in 28% of patients, and 16% showed retarded mental development. Bronchiectasis developed in 34%, and lymphoid proliferative disease in 13%. Incidence of allergic and autoimmune diseases was increased in first-degree relatives with normal immunologic findings. Mean time between symptoms and induction of immunoglobulin substitution therapy was 5.8 years (0.2-14.3).

CONCLUSIONS

CVID in children presents with comparable symptoms and disorders as in adults. We found a significant influence on growth and development. The marked delay of diagnosis may be due to overlap with common pediatric disorders, while also reflecting insufficient awareness of these disorders.

Long-term posaconazole treatment and follow-up of rhino-orbital-cerebral mucormycosis in a diabetic girl

To demonstrate that the 2-yr clinical follow-up of our patient strongly suggests that long-term therapy with posaconazole (POS) is safe and beneficial in treatment and prevention of relapses of, otherwise fatal, central nervous system mucormycosis. Mucormycosis is a very rare opportunistic mycotic infection of diabetic children. We present the 30-month follow-up of a 12-yr-old girl affected by diabetic ketoacidotic coma, complicated by rhinocerebral mucormycosis and successfully treated with POS at the initial daily dose of 5 mg/kg t.i.d. with fatty food for 3 wk, followed by a daily dose of 10 mg/kg in four doses for 2 months and then 20 mg/kg/d in four doses for 16 months and in two doses for further 5 months. The previous amphotericin B, granulocyte colony-stimulating factor, hyperbaric oxygen and nasal and left maxillary sinus surgical debridement therapy was ineffective in stopping the progression of the infection to the brain. The patient improved within 10 d with reduced ocular swelling and pain, and 6 months after therapy stop, she is in good health and cultures are sterile. This article demonstrates that POS may be a useful drug in mucormycosis in children. We also strongly draw the attention to the main preventive procedure against invasive fungal infection that is the correct management of antidiabetic therapy that prevents the predisposing temporary neutrophils activity deficit, contributing to a better survival rate of diabetic children.

Gene therapy for immunodeficiency due to adenosine deaminase deficiency

BACKGROUND

We investigated the long-term outcome of gene therapy for severe combined immunodeficiency (SCID) due to the lack of adenosine deaminase (ADA), a fatal disorder of purine metabolism and immunodeficiency.

METHODS

We infused autologous CD34+ bone marrow cells transduced with a retroviral vector containing the ADA gene into 10 children with SCID due to ADA deficiency who lacked an HLA-identical sibling donor, after nonmyeloablative conditioning with busulfan. Enzyme-replacement therapy was not given after infusion of the cells.

RESULTS

All patients are alive after a median follow-up of 4.0 years (range, 1.8 to 8.0). Transduced hematopoietic stem cells have stably engrafted and differentiated into myeloid cells containing ADA (mean range at 1 year in bone marrow lineages, 3.5 to 8.9%) and lymphoid cells (mean range in peripheral blood, 52.4 to 88.0%). Eight patients do not require enzyme-replacement therapy, their blood cells continue to express ADA, and they have no signs of defective detoxification of purine metabolites. Nine patients had immune reconstitution with increases in T-cell counts (median count at 3 years, 1.07x10(9) per liter) and normalization of T-cell function. In the five patients in whom intravenous immune globulin replacement was discontinued, antigen-specific antibody responses were elicited after exposure to vaccines or viral antigens. Effective protection against infections and improvement in physical development made a normal lifestyle possible. Serious adverse events included prolonged neutropenia (in two patients), hypertension (in one), central-venous-catheter-related infections (in two), Epstein-Barr virus reactivation (in one), and autoimmune hepatitis (in one).

CONCLUSIONS

Gene therapy, combined with reduced-intensity conditioning, is a safe and effective treatment for SCID in patients with ADA deficiency. (ClinicalTrials.gov numbers, NCT00598481 and NCT00599781.)

Insertional oncogenesis in 4 patients after retrovirus-mediated gene therapy of SCID-X1

Previously, several individuals with X-linked SCID (SCID-X1) were treated by gene therapy to restore the missing IL-2 receptor gamma (IL2RG) gene to CD34+ BM precursor cells using gammaretroviral vectors. While 9 of 10 patients were successfully treated, 4 of the 9 developed T cell leukemia 31-68 months after gene therapy. In 2 of these cases, blast cells contained activating vector insertions near the LIM domain-only 2 (LMO2) proto-oncogene. Here, we report data on the 2 most recent adverse events, which occurred in patients 7 and 10. In patient 10, blast cells contained an integrated vector near LMO2 and a second integrated vector near the proto-oncogene BMI1. In patient 7, blast cells contained an integrated vector near a third proto-oncogene,CCND2. Additional genetic abnormalities in the patients' blast cells included chromosomal translocations, gain-of-function mutations activating NOTCH1, and copy number changes, including deletion of tumor suppressor gene CDKN2A, 6q interstitial losses, and SIL-TAL1 rearrangement. These findings functionally specify a genetic network that controls growth in T cell progenitors. Chemotherapy led to sustained remission in 3 of the 4 cases of T cell leukemia, but failed in the fourth. Successful chemotherapy was associated with restoration of polyclonal transduced T cell populations. As a result, the treated patients continued to benefit from therapeutic gene transfer.

Insertional oncogenesis in 4 patients after retrovirus-mediated gene therapy of SCID-X1

Previously, several individuals with X-linked SCID (SCID-X1) were treated by gene therapy to restore the missing IL-2 receptor gamma (IL2RG) gene to CD34+ BM precursor cells using gammaretroviral vectors. While 9 of 10 patients were successfully treated, 4 of the 9 developed T cell leukemia 31-68 months after gene therapy. In 2 of these cases, blast cells contained activating vector insertions near the LIM domain-only 2 (LMO2) proto-oncogene. Here, we report data on the 2 most recent adverse events, which occurred in patients 7 and 10. In patient 10, blast cells contained an integrated vector near LMO2 and a second integrated vector near the proto-oncogene BMI1. In patient 7, blast cells contained an integrated vector near a third proto-oncogene,CCND2. Additional genetic abnormalities in the patients' blast cells included chromosomal translocations, gain-of-function mutations activating NOTCH1, and copy number changes, including deletion of tumor suppressor gene CDKN2A, 6q interstitial losses, and SIL-TAL1 rearrangement. These findings functionally specify a genetic network that controls growth in T cell progenitors. Chemotherapy led to sustained remission in 3 of the 4 cases of T cell leukemia, but failed in the fourth. Successful chemotherapy was associated with restoration of polyclonal transduced T cell populations. As a result, the treated patients continued to benefit from therapeutic gene transfer.

Disease progression in HIV-1 infected children and adolescents--results of a German-Austrian cohort study

OBJECTIVE

The Paediatric Working Group AIDS (PAAD) initiated a prospective cohort study in order to investigate disease progression in HIV- infected children and adolescents and the effect of antiretroviral treatment regimes.

PATIENTS AND METHODS

Between 1998 and 2003, paediatric centres documented HIV-infected patients under clinical care using a questionnaire for basic data and annual follow up. Main outcome measures were: use of antiretroviral therapy, adverse events, disease progression and change of therapeutic regimes.

RESULTS

174 HIV- infected paediatric patients were followed up in 12 centres in Germany and Austria between 1998 and 2003. Initially 54 (31%) patients had no antiretroviral therapy, 35 (20%) received a two-drug regimen (ART) and 85 patients (49%) a highly active antiretroviral therapy (HAART>or=3 drugs). After an observation period of 5 years, 8 patients (4%) had no therapy, 17 (10%) were on ART and 134 patients on HAART (77%). The number of patients with salvage therapy (>or=4 drugs) increased from 5 (3%) to 15 patients (9%). 72 of 166 treated patients (43%) had no change of their drug regimes, 68 patients (41%) had one change and 26 patients (16%)>or=2 changes. Main reasons for changes were increased viral load (49%), immunologic deterioration (21%) and adverse events (14%). During the follow up period no patient died. According to the CDC classification, disease progression was seen in 48 of 174 patients (28%), of whom 20 had deteriorations of clinical categories (A, B, C) and 28 of immunologic categories. Using Kaplan-Meier curves, the mean time from study onset until change of clinical categories was 61 months for patients on HAART, 26 months for patients on ART and 14 months for patients without ART.

CONCLUSION

In paediatric patients with HIV infection, disease progression has declined substantially by introduction of HAART. Superiority of HAART compared with ART was demonstrated. Non-adherence as well as other reasons for treatment failure have to be studied more carefully.

Haemophilus paraphrophilus, a rare cause of intracerebral abscess in children

We report on a 3-year-old boy presenting with left-sided eyelid myocloni due to an intracranial abscess harboring Haemophilus paraphrophilus. This is the first description of an intracranial infection with this pathogen in a child.

Dysregulation of innate immune receptors on neutrophils in chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease (CGD) is the most common inherited disorder of neutrophil function, is caused by mutations in the reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and results in recurrent bacterial infections.

OBJECTIVE

We sought to investigate the expression and function of innate immune receptors on neutrophils in patients with CGD.

METHODS

We quantified mRNA and protein expression of Toll-like receptors (TLRs), complement receptors, and chemokine receptors on neutrophils from 15 patients with CGD compared with that seen in healthy control subjects (n = 15) and control patients with bacterial pneumonia (n = 15). Phagocytosis, chemotaxis, and TLR function of isolated neutrophils were analyzed. The effect of NADPH oxidase inhibition on receptor expression and function was analyzed in control neutrophils.

RESULTS

Neutrophils from patients with CGD had lower expression levels of TLR5, TLR9, CD11b, CD18, CD35, and CXCR1 compared with those from healthy control subjects, whereas similar or increased receptor expressions were found in patients without CGD but with bacterial pneumonia. Reduced TLR5 expression resulted in impaired neutrophil activation by bacterial flagella, reduced CD11b/CD18 expression was associated with impaired phagocytosis of Staphylococcus aureus, and reduced CXCR1 expression was associated with decreased chemotaxis. TLR5 and CD18 expression levels correlated with disease severity in patients with CGD. TLR5 and TLR9 expression were greater in patients with residual NADPH oxidase activity. Inhibition of the NADPH oxidase in control neutrophils in vitro decreased TLR5 and TLR9 expression and impaired TLR5 function.

CONCLUSION

These results provide the first evidence that innate immune receptors are dysregulated in patients with CGD.

Lamivudine/abacavir maintains virological superiority over zidovudine/lamivudine and zidovudine/abacavir beyond 5 years in children

OBJECTIVE

To describe the long-term efficacy over 5 years of regimens including combinations of abacavir, lamivudine and/or zidovudine in previously untreated children in the PENTA 5 trial.

DESIGN

PENTA 5 was a 48-week randomised controlled trial comparing three dual nucleoside reverse transcriptase inhibitor (NRTI) combinations as part of first triple antiretroviral therapy (ART).

METHODS

128 ART-naïve children were randomised to zidovudine\lamivudine (n = 36), zidovudine\abacavir (45) or lamivudine\abacavir (47). Asymptomatic children (n = 55) were also randomised to nelfinavir or placebo; all other children received open-label nelfinavir. Analyses are intent-to-treat and adjusted for minor baseline imbalances and receipt of nelfinavir/placebo.

RESULTS

Median follow-up was 5.8 years. By 5 years, 17 (47%), 28 (64%) and 18 (39%) children had changed their randomised NRTIs in the zidovudine\lamivudine, zidovudine\abacavir and lamivudine\abacavir groups respectively, but 18%, 50% and 50% of these changes were either early single drug substitutions for toxicity or switches with viral suppression (HIV-1 RNA < 400 copies/ml; e.g. to simplify regimen delivery). At 5 years, 55%/32% zidovudine\lamivudine, 50%/25% zidovudine\abacavir and 79%/63% lamivudine\abacavir had HIV-1 RNA < 400/< 50 copies/ml respectively (p = 0.03/p = 0.003). Mean increase in height-for-age 0.42, 0.68, 1.05 (p = 0.02); weight-for-age 0.03, 0.13, 0.75 (p = 0.02). Reverse transcriptase resistance mutations emerging on therapy differed between the groups: zidovudine\lamivudine (M41L, D67N, K70R, M184V, L210W, T215Y); zidovudine\abacavir (M41L, D67N, K70R, L210W, T215F/Y, K219Q); lamivudine\abacavir (K65R, L74V, Y115F, M184V).

CONCLUSIONS

Five year data demonstrate that lamivudine\abacavir is more effective in terms of HIV-1 RNA suppression and growth changes, with lower rates of switching with detectable HIV-1 RNA than zidovudine\lamivudine or zidovudine\abacavir, and should be preferred as first-line NRTI backbone.

Mimotopes selected with antibodies from HIV-1-neutralizing long-term non-progressor plasma

A promising approach to identify HIV-1 vaccine candidates is to dissect the natural immune response against the virus in persons controlling the infection over decades without any antiviral therapy. Here we focus on a group of such persons, eight long-term non-progressors (LTNP), in which we proved the presence of broadly neutralizing antibodies against HIV-1 in the plasma as very likely cause for their LTNP status. The aim of this study was to identify the epitopes for these neutralizing antibodies, as these should represent immunogens potentially able to elicit neutralizing antibodies upon vaccination. We screened random peptide phage libraries with plasma antibodies from eight LTNP. After several rounds of positive and negative selection, about 700 HIV-specific mimotopes were sequenced. The mimotope sequences were analyzed for homology to HIV-1 Env, in particular for their capacity to represent conformational epitopes on the surface of the gp120 structure using our software 3DEX. Related phage groups were analyzed for crossreactivity with the LTNP plasma by ELISA as well as for their capacity to induce HIV-1-neutralizing antibodies in mice. Based on this study interesting mimotopes can now be selected for further immunization studies.

"Hair-on-end" skull induced by long-term G-CSF treatment in severe congenital neutropenia

"Hair-on-end" skull changes are typically seen in individuals suffering from thalassaemia. They are induced by widening of the diploic space due to marrow expansion that is a consequence of ineffective and excessive erythropoiesis. We present a child with severe congenital neutropenia who exhibited the typical hair-on-end sign on plain skull radiographs and MRI. In this patient the skull changes were very likely induced by the expansion of white blood cell precursors induced by long-term daily injections of recombinant human granulocyte colony stimulating factor (G-CSF) to treat his confounding disease. This case report is the first description of hair-on-end changes associated with the use of G-CSF.

Posaconazole for treatment of refractory invasive fungal disease

Invasive fungal infections are usually associated with immunocompromised states About 40-60% of these patients are refractory to standard antifungal therapy We describe the effect of posaconazole in the treatment of a 12 years-old girl with uncontrolled diabetes mellitus with life-threatening cerebral mucor mycosis and a 4 year old girl boy with chronic granulomatous disease presenting with invasive Aspergillus nidulans infection.

Effect of first line therapy including efavirenz and two nucleoside reverse transcriptase inhibitors in HIV-infected children

OBJECTIVE

In an intent-to-treat study, reduction of viral load, increase in CD4 cell count, clinical benefit and adverse reactions were examined in HIV-infected children receiving first line therapy including efavirenz.

METHODS

The data of 10 perinatally infected children (median age: 5.8 years) were evaluated during a treatment period of 24 months. Viral load and CD4 cell count were measured every 4 - 8 weeks. Pharmacokinetic evaluations of efavirenz were performed in all patients at study onset. Adverse reactions were reported after obtaining interval history and examination.

RESULTS

At base line, median CD4 cell count was 378 cells/microl (21%) and median viral load was 350,000 copies/ml (5.5 log10 copies/ml). After 24 months of treatment, the median viral load reduction was > 3.5 log10 copies/ ml and HIV-1 RNA < 50 copies/ml was found in 8/10 children (80%). Median CD4 cell count increased to 721 cells/microl (24%) after 3 months and was maintained at a level of >1000 cells/microl (> 25%) after 24 months of treatment. Regarding efavirenz levels, C min. values ranged from 845 to 3550 ng/ml (median: 1845 ng/ml) and C max. values from 2380 to 24 200 ng/ ml (median: 3670 ng/ml). The most common adverse effect was a mild skin rash (4/10 children). CNS symptoms were recorded in one patient and no hyperlipidaemia was seen.

CONCLUSION

First line therapy with efavirenz and two NRTIs was well tolerated by HIV-1 infected children and the reduction of viral load seems to be similar to single protease inhibitor-containing regimens.

Therapy of focal viral encephalitis in children with aciclovir and recombinant beta-interferon - results of a placebo-controlled multicenter study

Focal viral encephalitis in childhood is a rare but life-threatening disease. Animal experiments and case reports suggest a positive effect of an additional therapy with interferon-beta on the course of the disease. Therefore, we initiated a prospective, double-blind placebo-controlled study to investigate the benefit of a combination therapy of Aciclovir (ACV) and recombinant interferon-beta (rIFN-beta) in juvenile focal viral encephalitis. - Initial inclusion criterium was suspicion of focal viral encephalitis. Diagnosis was proven by demonstration of characteristic focal lesions in cerebral imaging or virological evidence of HSV in cerebrospinal fluid. Patients were treated with ACV plus rIFN-beta or ACV plus placebo. Neurological outcome was determined 21 days and 3 months after onset of the disease. - Initially 59 patients were enrolled in the study. Encephalitis was proven in 14 patients (7 ACV + rIFN-beta, 7 ACV + placebo). The study groups were balanced in terms of important prognostic criteria. 10 patients (5 ACV + rIFN-beta, 5 ACV + placebo) were cured or had slight defects, 4 patients (2 ACV + rIFN-beta, 2 ACV + placebo) showed moderate to severe defects. There was no significant difference in favour of the additive therapy with rIFN-beta.

Withdrawal of Pneumocystis jirovecii prophylaxis in HIV-infected children under highly active antiretroviral therapy

OBJECTIVE

In HIV-infected adults Pneumocystis jirovecii pneumonia (PCP) prophylaxis can be safely withdrawn after immune reconstitution due to the introduction of highly active antiretroviral therapy (HAART). With regard to children only a small amount of data has been published. The present study investigated whether the withdrawal of PCP prophylaxis after immune reconstitution is safe in HIV-infected children.

METHODS

A retrospective analysis at 10 European centers belonging to the Pediatric European Network on the treatment of AIDS (PENTA) using a standardized questionnaire.

RESULTS

A total of 113 questionnaires were received. In 82 children the indication for PCP prophylaxis was provided following Centers for Disease Control (CDC) guidelines (72 primary and 10 secondary). Prophylaxis was withdrawn after the CD4 cell count increased above the age-related CDC thresholds. The observation period off prophylaxis was 335 years (300 years for primary and 35 years for secondary prophylaxis) and the median time per patient off prophylaxis was 4.1 years (range, 0.3-7.7 years). No episode of PCP occurred during the study period. In comparison with the incidence rate from historical data before the introduction of PCP prophylaxis and HAART, this was a significant reduction (P < 0.05).

CONCLUSIONS

The increase in CD4 cell count provides functional reconstitution of the immune system in children. Our data suggests that the risk of developing a PCP after immune reconstitution is sufficiently low to withdraw PCP prophylaxis.

A donor splice site mutation in intron 1 of CYBA, leading to chronic granulomatous disease

Chronic granulomatous disease (CGD) is a rare congenital disorder in which the patients' phagocytes fail to kill ingested microbes due to an inability to generate superoxide and other microbicidal oxygen derivatives. This inability is caused by mutations in one of the four components of the phagocyte-specific NADPH oxidase. A small subgroup of CGD patients has mutations in the CYBA gene that encodes the p22-phox subunit of the NADPH oxidase. This subunit forms, together with gp91-phox, a flavocytochrome b(558) heterodimer in the phagocyte plasma membrane. Expression of both subunits is required for normal expression of this heterodimer. Here, we report an autosomal recessive CGD patient with neutrophils that did not express flavocytochrome b(558) and did not generate superoxide upon activation. Analysis of genomic DNA revealed a 4-bp deletion at the exon-1/intron-1 boundary in CYBA (IVS1+4_7delAGTG). In the patient's cDNA, we found a low expression of an abnormal product, containing exon 1 extended by 79 nucleotides from intron 1, joined to exon 2. This extension is apparently caused by the activation of a cryptic donor splice site with a GT sequence at position 84-85 in intron 1. Both parents of the patient had the same mutation in their genomic DNA, in heterozygous form, but their cDNA contained exclusively the wild-type p22-phox cDNA sequence, indicating that the mutant mRNA was labile. This is, as far as we know, the first description of the molecular and clinical consequences of a donor splice site mutation in intron 1 of any gene reported so far.

[Treatment of primary immune defects]

Management of immunodeficient patients includes monitoring of growth, diet, personal hygiene and life habits, including environmental factors. Major therapeutic stays are prevention, early detection and the decisive treatment of infections. Attenuated live vaccines, non-irradiated blood products and blood containing CMV antibodies should not be applied. In the case of antibody defects immunoglobulin substitution is a specific form of treatment. Enzyme replacement is a causal approach to an adenosine deaminase defect. For numerous primary immune defects, bone marrow transplantation represents the best causal therapeutic measure. In the absence of a bone marrow donor, alternative gene therapy is available for the management of severe combined immunodeficiency on the X-chromosome (X-SCID), and adenosine deaminase deficiency (ADA deficiency).

[Could it be an immune defect? Background and diagnosis]

With modern immunological and molecular biological laboratory techniques, some 100 primary immunodeficiencies can now be diagnosed and differentiated. The importance of diagnosing a primary immunodeficiency (PID) as early as possible cannot be overemphasized. In patients with PID, recurrent infections can lead to permanent damage and sometimes even to death. On the occasion of a first visit to the physician, the patient usually presents with nonspecific symptoms, in particular recurrent infections, a challenging situation in terms of making the correct diagnosis. Relevant warning signals and a possible family history should also prompt at least such simple laboratory tests as a blood differential and the quantitative determination of immunoglobulins, followed where necessary by more specific evaluations. Early treatment, for example, with immunoglobulins may enable many patients to lead a virtually normal life, and in some cases bone marrow transplantation or gene therapy may even result in a cure.

Relationship between Changes in Thymic Emigrants and Cell-Associated HIV-1 Dna in HIV-1-Infected Children Initiating Antiretroviral Therapy

Objectives and methods

To investigate the relationship between cell-associated HIV-1 dynamics and recent thymic T-cell emigrants, HIV-1 DNA and T-cell receptor rearrangement excision circles (TREC, a marker of recent thymic emigrants) were measured in peripheral blood mononuclear cells in 181 samples from 33 HIV-1-infected children followed for 96 weeks after antiretroviral therapy (ART) initiation.

Results

At baseline, HIV-1 DNA was higher in children with higher TREC ( P=0.02) and was not related to age, CD4 or HIV-1 RNA in multivariate analyses ( P>0.3). Overall, TREC increased and HIV-1 DNA decreased significantly after ART initiation, with faster HIV-1 DNA declines in children with higher baseline TREC ( P=0.009). The greatest decreases in HIV-1 DNA occurred in children with the smallest increases in TREC levels during ART ( P=0.002). However, this inverse relationship between changes in HIV-1 DNA and TREC tended to vary according to the phase of HIV-1 RNA decline ( P=0.13); for the same increase in TREC, HIV-1 DNA decline was much smaller during persistent or transient viraemia compared with stable HIV-1 RNA suppression.

Conclusions

Overall, these findings indicate that TREC levels predict HIV-1 DNA response to ART and suggest that immune repopulation by thymic emigrants adversely affects HIV-1 DNA decline in the absence of persistent viral suppression, possibly by providing a cellular source for viral infection and replication.

Celiac disease and pulmonary hemosiderosis in a patient with chronic granulomatous disease

We report on a patient with the hitherto undescribed combination of chronic granulomatous disease, pulmonary hemosiderosis, and celiac disease. The hemosiderosis resolved with a gluten-free diet and glucocorticosteroid pulse therapy, but the restrictive lung function pattern remained unchanged. Lung function improved markedly by immunosuppression with daily glucocorticosteroid and azathioprine treatment.

Long-term pharmacokinetics of amprenavir in combination with delavirdine in HIV-infected children

Five heavily pretreated HIV-infected children were put on amprenavir and delavirdine plus two nucleoside inhibitors to reverse transcriptase to boost amprenavir levels and to use the antiretroviral activity of a non-nucleoside reverse transcriptase inhibitor. No data are available about this combination in children. It w;as well tolerated, and the median reduction in viral load was 1.5 log after 18 months. Delavirdine boosted amprenavir trough levels more than 10-fold, and delavirdine trough levels remained i several fold above susceptible HIV strains.

LMO2-associated clonal T cell proliferation in two patients after gene therapy for SCID-X1

We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gamma(c)) deficiency] in 9 out of 10 patients by retrovirus-mediated gamma(c) gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.

Macrophages of patients with X-linked thrombocytopenia display an attenuated Wiskott-Aldrich syndrome phenotype

The immunodeficiency disorder Wiskott-Aldrich syndrome and its milder form X-linked thrombo-cytopenia are caused by mutations in the WASp gene. Wiskott-Aldrich syndrome is characterized by a plethora of clinical symptoms which are due to functional defects of haematopoietic cells, including the inability of macrophages to form actin-rich adhesion structures called podosomes. In contrast, X-linked thrombocytopenia patients show reduced platelet size and counts but no cytoskeletal white blood cell defects have been detected so far. Here we use immunofluorescence technique to evaluate podosome formation in macrophages from X-linked thrombocyto-penia and Wiskott-Aldrich syndrome patients and from healthy donors. We find that X-linked thrombocytopenia macrophages, cells previously thought to be unaffected in this disorder, are compromised in the formation of podosomes. Western blot analysis shows that this phenotype is not due to lower levels of WASp expression. Interestingly, the bacterial chemoattractant formyl-methionyl-leucyl-phenylalanine can rescue podosome formation in X-linked thrombocytopenia cells. Our findings indicate that: 1. The spectrum of WASp-dependent disorders contains defects more subtle than originally recognized and 2. in X-linked thrombocytopenia, some of these defects may not be evident under conditions of bacterial stimulation. Further evaluation of this and other, as yet unrecognized, cellular defects may provide a more complete picture of the continuum of Wiskott-Aldrich syndrome and X-linked thrombocytopenia defects.

Effect of antiretroviral triple combinations including the protease inhibitor nelfinavir in heavily pretreated children with HIV-1 infection

BACKGROUND

In this retrospective study the effect of antiretroviral triple therapy including the protease-inhibitor nelfinavir (NFV) on CD4-cells and viral load (VL) in heavily pretreated HIV-infected children was evaluated.

PATIENTS AND METHODS

20 children (<18 years) were included. Median duration of antiretroviral pretreatment was 27 months (range, 7 65), median initial VL was 4.7 log subset 10 (3.2 6.1) and median relative CD4-cells was 17.5% (3 33). Patients were put on combinations with NFV because of treatment failure (increasing VL), intolerance to prior therapy with PIs or adherence problems with prior indinavir. Viral load (RT-PCR, detection limit 50 copies/ml) and CD4-cells were measured every 4-8 weeks.

RESULTS

Median viral load decreased 1.2 log(10) (-1.3 2.5), 0.9 log(10) (-0.8 - 2.5) and 0.4 log(10) (-0.5 - 3.0) after 12, 24 and 36 weeks. The VL of 2 patients was below the detection limit (50 copies/ml) after 24 weeks. The relative CD4-cell count increased from a median of 17.5% to 22%, 23% and 25% after 12, 24 and 36 weeks, respectively. Side effects of NFV were usually mild. WHO grade 1 or 2 diarrhea occurred in 70% and moderate elevations of triglycerides in 40% of the patients. At 48 weeks 18/20 patients had to be switched to other combinations due to virological failure.

CONCLUSIONS

In children with intensive prior antiretroviral therapy combination therapy including NFV lead to a modest short-term reduction of the VL and increase in CD4-cells. However, the long-term antiretroviral effect was poor.

Effect of antiretroviral combination therapies including efavirenz in heavily pretreated HIV-infected children

BACKGROUND

In this retrospective study the effect of antiretroviral combination regimens including the non nucleoside reverse transcriptase inhibitor (NNRTI) efavirenz (EFV) on viral load (VL) and CD4-cell count in heavily pretreated HIV-infected children was investigated.

DESIGN

The data of 15 children (< 16 years) were evaluated during a treatment period of at least 52 weeks. Patients received a median of 4 prior antiretroviral regimens and were changed to combinations with EFV because of renewed increasing VL.

METHODS

Viral load (Amplicor, detection limit 50 copies/ml) and CD4-cells were measured every 4-8 weeks.

RESULTS

The median reduction of the viral load for the total study population was 1.9 log10 (0.8 - 4.7), 2.3 log(10) (0.5 - 4.7) and 2.6 log(10) (0-4.7) after 12, 24 and 52 weeks, respectively. After 24 weeks 7/15 children and after 52 weeks 9/15 patients had reductions of the VL below the detection limit. The median increase of CD4-cells in the study population during the treatment period were 104 cells/microl (189-969), 220 cells/microl (170-831) and 321 cells/ml (162-574) after 12, 24 and 52 weeks, respectively.

CONCLUSIONS

In children with intensive prior antiretroviral therapy and multiple therapeutic failures with PI-containing regimens, combination therapy including EFV resulted in an excellent antiretroviral efficacy. After 52 weeks 9/15 patients had persistent reductions of the VL below 50 copies/ml, although none of these children reached this level of viral suppression during their multiple prior protease inhibitor-containing regimens.