[Screening investigations during intensified immunosuppression in children and adolescents. Part 1]. / Vorsorgeuntersuchungen während intensivierter Immunsuppression bei Kindern und Jugendlichen. Teil 1.

The increasing use of combination therapies, including disease-modifying antirheumatic drugs (DMARD) and biologicals has improved the outcome for children and adolescents in several rheumatic diseases. However, this strategy has increased the risk of drug-specific side-effects, such as an increased risk of infections. Furthermore, the underlying rheumatic disease itself often includes an increased risk of infections and some patients additionally present with immunological or organic comorbidities (e.g. complement deficiency and interstitial pulmonary disease) further increasing the susceptibility to infections. The presented review is based on an analysis of the currently available literature proposing a checklist of diagnostic procedures and immunological laboratory tests specific for the detection of patients prone to infections. The combined stratification of the underlying disease, comorbidities and the immunological mechanisms of the medication enables (1) an individual risk stratification of planned immunosuppressive therapy and (2) a prediction of the risks of infection for the patient.

[Medicinal prophylaxis during intensified immunosuppression in children and adolescents : part 2]. / Medikamentöse Prophylaxe während intensivierter Immunsuppression bei Kindern und Jugendlichen : Teil 2.

The goal of modern antirheumatic therapy is to achieve an optimized disease control. This is individually achieved by an intensified immunosuppression (IS) frequently combining different immunosuppressive agents. Intensified IS should be accompanied by a standardized protocol to monitor immunological changes in the patient. This should include checklists (see Part 1 Screening during intensified IS in children and adolescents). An individual risk stratification according to the planned IS allows a prediction of infectious disease risks for the patient and, thus, individual infection prophylaxis. In addition, standardized management of patients with fever while receiving intensified IS may prevent further complications.

[Laboratory survey on the incidence of Pneumocystis jirovecii - obviously a peculiar fungus, but also a rare pathogen?]. / Laborerhebung zur Häufigkeit von Pneumocystis jirovecii - Zwar ein besonderer Pilz, aber auch ein seltener Erreger?

Pneumocystsis jirovecii is a peculiar fungus for a variety of reasons. This opportunistic pathogen multiplies in humans only under certain conditions; a defect in the T-cell defense system creates a predisposition to this infection. In 2010 a data survey (IFT as well as PCR) from a few laboratories in Germany revealed 412 positive individuals. Even if only a few patients test positive for the colonization stage of this pathogen, the sheer number of individuals testing positive for other stages of infection indicate that the incidence of pneumocystosis in immunocompromised patients in Germany is underestimated.

Is domestic tap water a risk for infections in neutropenic patients?

BACKGROUND: Home care has become popular in the management of hemato-oncologic patients. Therefore, we conducted a prospective study to assess whether tap water from the domestic environment of neutropenic patients poses a risk for infections from the waterborne pathogens nontuberculous mycobacteria (NTM), Legionella spp., and Pseudomonas aeruginosa. MATERIALS AND METHODS: Tap water samples were taken in the homes of 65 hemato-oncologic patients who were discharged from the hospital whilst neutropenic and had a suspected period of neutropenia of a minimum of 10 days. Selective culture for Legionella, P. aeruginosa, and NTM was performed. Patients who required hospital readmission were monitored for infection with the aforementioned pathogens over the following 3 months. RESULTS: NTM were cultured in 62 (95.4%) households in concentrations from 1 to 1,000 CFU/500 ml. The facultative pathogenic species Mycobacterium chelonae (58.5% of taps) and M. mucogenicum (38.5% of taps) were most frequently detected. Legionella spp. was cultured from six households (9.2%), including five households with L. pneumophila in concentrations from 25 to 2,500 CFU/500 ml. P. aeruginosa was found in seven households (10.8%) in concentrations from 5 to 2,500 CFU/500 ml. While clinical infection with Legionella spp. was not detected in any patients, infection with M. chelonae and P. aeruginosa occurred in one and seven patients, respectively. However, transmission from household water could not be confirmed. CONCLUSION: Although the risk of infection from household water-borne pathogens appears low, preventive measures may be considered on an individual basis in patients with long-term immunosuppression as well as in patients with long-term central-vascular catheterization.

Habitat fragmentation and haemoparasites in the common fruit bat, Artibeus jamaicensis (Phyllostomidae) in a tropical lowland forest in Panamá.

Anthropogenic influence on ecosystems, such as habitat fragmentation, impacts species diversity and interactions. There is growing evidence that degradation of habitats favours disease and hence affects ecosystem health. The prevalence of haemoparasites in the Common Fruit Bat (Artibeus jamaicensis) in a tropical lowland forest in Panamá was studied. We assessed the relation of haemoparasite to the general condition of the animals and tested for possible association of haemoparasite prevalence to habitat fragmentation, with special focus on trypanosomes. Overall, a total of 250 A. jamaicensis sampled from fragmented sites, here man-made, forested islands in Lake Gatùn, and sites in the adjacent, continuous forest in and around the Barro Colorado Nature Monument were examined. Using microscopy and DNA-sequencing 2 dominant types of haemoparasite infections, trypanosomes and Litomosoides (Nematoda) were identified. Trypanosome prevalence was significantly higher in bats from forest fragments, than in bats captured in continuous forest. We attribute this to the loss of species richness in forest fragments and specific characteristics of the fragments favouring trypanosome transmission, in particular changes in vegetation cover. Interestingly, the effect of habitat fragmentation on the prevalence of trypanosomes as multi-host parasites could not be observed in Litomosoides which probably has a higher host specificity and might be affected less by overall diversity loss.

Rapid detection of Staphylococcus aureus bacteremia and methicillin resistance by real-time PCR in whole blood samples.

We prospectively evaluated a real-time polymerase chain reaction (PCR) approach for the rapid diagnosis of Staphylococcus aureus bacteremia and presence of the mecA gene in 902 blood samples from 468 infectious episodes of 384 patients. Eight of 12 blood culture (BC)-confirmed samples were positive by the S. aureus-specific PCR. In addition, the mecA gene PCR correctly detected all cases of BC-confirmed methicillin-resistant Staphylococcus aureus (MRSA) infection. A positive PCR result was also obtained in ten of 462 BC-negative infectious episodes, including three patients with culture-confirmed S. aureus infection at other body sites.

Staphylococcus aureus in nasal lavage and biopsy of patients with chronic rhinosinusitis.

BACKGROUND: Staphylococcus aureus may play a relevant etiologic role in chronic rhinosinusitis (CRS) and may explain the T(H2) shift observed in CRS with nasal polyps (CRSNP(+)). Naturally occurring S. aureus small colony variants (SASCV) escape immune surveillance, antibiotic treatment and microbiologic routine diagnostic techniques. The frequency of S. aureus and SASCV in CRS patients and S. aureus-related effects on the local immune response should be prospectively investigated. METHODS: Nasal lavages and mucosal biopsies of CRS patients were examined with bacterial culture suitable for detecting SASCV, real time PCR and fluorescence in situ hybridization. To assess the effects of S. aureus positivity, interleukin-5 (IL-5), interferon-gamma, total immunoglobulin E (IgE), eotaxin, granulocyte-colony stimulating factor, and eosinophil cationic protein in nasal lavages were determined and gene transcription analysis of nasal biopsies from S. aureus positive and negative CRSNP(+) patients was performed. RESULTS: Thirty-one CRSNP(+) patients, 13 CRS patients without polyps, and 21 control patients were evaluated. Staphylococcus aureus was detected by any method in 25 patients (39%). Staphylococcus aureus detection rates did not differ between the three disease groups (P = 0.3). Staphylococcus aureus small colony variants were not found. In nasal lavages, IL-5 and total IgE levels were higher in CRSNP(+) patients than in CRSNP(-) patients or controls (P < 0.05). Staphylococcus aureus positivity did not influence biomarker concentrations in nasal lavages. Genes for T(H2) cytokines were not differentially transcribed. CONCLUSIONS: We could not observe a higher prevalence of S. aureus in CRS patients with or without nasal polyps than in controls. We could not substantiate that S. aureus intensifies the T(H2) shift in CRSNP(+) patients. Staphylococcus aureus small colony variants were not detected in any sample.

Evidence of coinfection with distinct strains of Burkholderia multivorans in a cystic fibrosis patient.

We report a Cystic Fibrosis patient with chronic Burkholderia multivorans infection involving persistency of one strain and temporary, consecutive coinfection with two different strains. Comparison of the colony morphology with the genotype revealed no correlation. These data are important for interpretation of clinical outcome and transmission studies in CF patients.

[Cat-scratch disease as cause of Lymphadenitis colli]. / Katzenkratzkrankheit als Ursache einer Lymphadenitis colli.

Cat-scratch Disease as Cause of Lymphadenitis colli. Cat-scratch disease is a frequent cause of lymphadenitis colli. It mainly affects children and adolescents younger than 21 years. Since the clinical picture is not characteristic, a history of contact to cats or kittens is highly valuable for diagnosing the disease. Major aspects of the disease concerning epidemiology, diagnostic procedures, clinical presentation and therapy are discussed.

Detection of legionellae in hospital water samples by quantitative real-time LightCycler PCR.

Contamination of hospital water systems with legionellae is a well-known cause of nosocomial legionellosis. We describe a new real-time LightCycler PCR assay for quantitative determination of legionellae in potable water samples. Primers that amplify both a 386-bp fragment of the 16S rRNA gene from Legionella spp. and a specifically cloned fragment of the phage lambda, added to each sample as an internal inhibitor control, were used. The amplified products were detected by use of a dual-color hybridization probe assay design and quantified with external standards composed of Legionella pneumophila genomic DNA. The PCR assay had a sensitivity of 1 fg of Legionella DNA (i.e., less than one Legionella organism) per assay and detected 44 Legionella species and serogroups. Seventy-seven water samples from three hospitals were investigated by PCR and culture. The rates of detection of legionellae were 98.7% (76 of 77) by the PCR assay and 70.1% (54 of 77) by culture; PCR inhibitors were detected in one sample. The amounts of legionellae calculated from the PCR results were associated with the CFU detected by culture (r = 0.57; P < 0.001), but PCR results were mostly higher than the culture results. Since L. pneumophila is the main cause of legionellosis, we further developed a quantitative L. pneumophila-specific PCR assay targeting the macrophage infectivity potentiator (mip) gene, which codes for an immunophilin of the FK506 binding protein family. All but one of the 16S rRNA gene PCR-positive water samples were also positive in the mip gene PCR, and the results of the two PCR assays were correlated. In conclusion, the newly developed Legionella genus-specific and L. pneumophila species-specific PCR assays proved to be valuable tools for investigation of Legionella contamination in potable water systems.

Immunobiology of gestational zinc deficiency.

The trace element zinc is an essential micronutrient for the proper functioning of the immune system. Zinc deficiency leads to impaired function of the unspecific and specific immune response and consequently to an increased susceptibility to bacterial, viral and fungal infections. Immunological defects are not only seen in pronounced but even in marginal and moderate zinc deficiency. Lack of zinc is especially harmful for the development of the immune system, which stresses the importance of a balanced zinc level during pregnancy. However, gestational zinc deficiency due to an imbalance between intake and increased requirements is a common problem world-wide. In animals, gestational zinc deficiency results in reduced thymic and spleen size and depressed active and passive immunity in the infant. For example, depressed immunoglobulin levels, altered antibody repertoire, reduced proliferative response of lymphocytes and diminished neutrophil functions have been reported. Interestingly, immune defects caused by prenatal zinc deficiency, such as depressed antibody levels and lymphocyte proliferation, may even persist in subsequent generations and are not reversible by postnatal zinc administration. Since gestational zinc deficiency is a common problem throughout all cultures and socioeconomic levels, it might have immense consequences for the health status of the population. Based on a summary of the immunobiology of zinc, this article reviews the significance of zinc deficiency during pregnancy and the effect of gestational zinc deficiency on passive and active immunity in the infant. It provides a rational basis for both immunological laboratory investigations and field studies, such as large community-based zinc supplementation trials in pregnant women.

A new ImmunoCAP assay for detection of Echinococcus multilocularis-specific IgE.

In alveolar echinococcosis (AE), caused by Echinococcus multilocularis (E.m.), increased levels of total and parasite-specific IgE are frequently found. These may not only have diagnostic but are also supposed to have prognostic value in the follow-up of AE patients. However, there is no commercial test available for quantification of E. m.-specific IgE (sIgE). The only commercial test available is based on E. granulosus (g.) hydatid antigen, which is not optimal for detection of E. m.-specific IgE. Therefore, a new ImmunoCAP with covalently bound crude antigen of E. m. was developed in cooperation with Pharmacia Research Forum for the analysis of E. m. sIgE. The E. m. ImmunoCAP was evaluated in 53 AE patients with different clinical disease progression and 20 healthy controls. Our data showed a higher sensitivity for sIgE determination with E. m. ImmunoCAP compared to the E. g. ImmunoCAP (73.6% vs 61.5%) and a positive correlation between total IgE and sIgE. Furthermore, there was a significant correlation between sIgE in both tests. In conclusion, the new E. m.-specific ImmunoCAP test proved to be a valuable tool for determination of sIgE. It may provide the basis for the development of further E. multilocularis-specific IgE immunotests which are essential for evaluation of sIgE during clinical course of AE.

Zinc inhibits the mixed lymphocyte culture.

The mixed lymphocyte culture (MLC) is an established clinical method for bone marrow transplantation, as it serves as an in vitro model for allogenic reaction and transplantation. We previously showed that cytokine release into the supernatant is a more specific and sensitive parameter for cross-reactivity in the MLC than the common measurement of cell proliferation. Therefore we tried to find an inhibitor of the MLC in vitro with the least side effects in vivo, measuring interferon (IFN)-gamma as one of the most important cytokines in posttransplant medicine. Earlier studies showed that zinc is an important trace element for immune function with both stimulatory and inhibitory effects on immune cells. We found that slightly elevated zinc concentrations (three to four times the physiological level), which do not decrease T-cell proliferation in vitro nor produce immunosuppressive effects in vivo, suppress alloreactivity in the mixed lymphocyte culture. In this report we analyzed the mechanism whereby zinc influences the MLC to possibly find a nontoxic way of immunosuppression.

Zinc serum level in human immunodeficiency virus-infected patients in relation to immunological status.

In human immunodeficiency virus (HIV) infection, serum level of zinc, an important micronutrient for immune function, is frequently diminished. The aim of this study was to determine the zinc status in relation to immunological parameters and disease stage in 79 HIV-1 seropositive patients. The median serum level of zinc was within normal limits (12.5 micromol/L) but in 23% of patients, zinc deficiency was seen. Decreased serum zinc was associated with a low CD4 cell count, high viral load, and increased neopterin and IgA levels. According to current treatment recommendations, the majority of patients received antiretroviral triple therapy. Zinc levels in treated and untreated patients were comparable. Referring to disease stage (CDC classification, 1993), the mean zinc level was highest in stage C and lowest in stage A. In conclusion, even under antiretroviral triple therapy, zinc deficiency is still of great importance in HIV infection, and zinc substitution in zinc deficient individuals should be taken into account to optimize therapeutical success.

Increased levels of soluble Fas ligand in serum in Plasmodium falciparum malaria.

Levels of soluble Fas ligand (sFasL) in serum were elevated in patients with Plasmodium falciparum malaria and showed a significant decline during disease course. sFasL levels that were elevated before antimalarial treatment began correlated significantly with depressed total lymphocyte and T-cell counts. These data suggest that Fas-induced apoptosis might play a role in malaria-associated lymphopenia.

Interleukin (IL)-4, IL-10 and IL-12 profile in serum of patients with alveolar echinococcosis.

Alveolar echinococcosis (AE), caused by Echinococcus multilocularis (E.m.), provokes a characteristic immune response. Based mainly on in vitro studies, Th2 dominated immunity is associated with increased susceptibility to disease, while Th1 cell activation is assumed to induce protective immunity. We investigated serum levels of interleukin (IL)4, IL-10, and IL-12 in 40 AE patients and 20 controls to assess Th1/Th2 cell activation in vivo. Significantly higher levels of IL-10 were found in AE patients (P = 0.003) than in controls, with a tendency to higher concentrations in progressive cases. In contrast, IL-4 was only measurable in a minority of patients and controls. IL-12 levels (measured with an ELISA that detects both the p35/p40 heterodimer and free p40) were comparable between AE patients and controls and showed a similar distribution pattern to IL-10 with regard to disease progression. By using an IL-12-ELISA specific for the heterodimer, only minute amounts of IL-12 were detectable in merely a minority of samples. In conclusion, our data are suggestive of Th2 dominated immune response in AE in vivo.

Genetic linkage of hyper-IgE syndrome to chromosome 4.

The hyper-IgE syndrome (HIES) is a rare primary immunodeficiency characterized by recurrent skin abscesses, pneumonia, and highly elevated levels of serum IgE. HIES is now recognized as a multisystem disorder, with nonimmunologic abnormalities of the dentition, bones, and connective tissue. HIES can be transmitted as an autosomal dominant trait with variable expressivity. Nineteen kindreds with multiple cases of HIES were scored for clinical and laboratory findings and were genotyped with polymorphic markers in a candidate region on human chromosome 4. Linkage analysis showed a maximum two-point LOD score of 3.61 at recombination fraction of 0 with marker D4S428. Multipoint analysis and simulation testing confirmed that the proximal 4q region contains a disease locus for HIES.

Zinc status in patients with alveolar echinococcosis is related to disease progression.

Zinc is an essential trace element for immune function that plays a role in immune response against parasites. To determine a possible relationship between zinc level and disease status in alveolar echinococcosis (AE), we investigated serum concentrations of zinc, immunoglobulin (Ig)E, IgG, and C-reactive protein (CRP) in 40 AE patients and 20 controls. Patients were classified into three groups: group A: patients after curative surgery, group B: patients with stabilized disease, group C: patients with progressive disease. Patients showed significantly higher levels of IgE and IgG than controls. Amounts of IgE and IgG were related to disease severity, achieving highest levels in group C and lowest in group A. Zinc levels were comparable in patients and controls. However, there was an obvious association between zinc concentration and disease severity. Zinc was far below the normal range in group C (median 9.2 micromol/l) and significantly diminished compared to group B and controls. An inverse pattern was seen for CRP. In conclusion, lowered zinc concentration in progressive cases may be caused by enhanced immune activation but consumption of zinc by the growing parasite may also play a role. Furthermore, decreased zinc levels may contribute to the observed immunosuppression in AE.

The significance of zinc for leukocyte biology.

Zinc is an essential element important for growth, the nervous system, and especially the immune system. Zinc deficiency as well as levels well above normal, due to high-dose treatment, showed an impaired immune function. This review summarizes the current status of zinc's significance for leukocyte biology and health. In detail, the physiology of zinc and the impaired immune functions in zinc deficiency syndromes are described. The regulation of innate immunity as well as the function and maturation of lymphocytes and monocytes is critically discussed as a system dependent on the zinc concentration in vivo and in vitro. Furthermore, the influence of zinc on experimental systems as well as on widely used immunostimulants is described, showing the importance of the knowledge of zinc concentration in in vitro leukocyte studies. The specific interactions of zinc with immunologically important serum proteins, signal transduction components, and membrane functions is summarized, showing the molecular basis of this interaction as known so far. Finally, the therapeutic use of zinc is critically discussed with new aspects also using the immunosuppressive effects of zinc. In conclusion, these data show that the zinc concentration should be taken into account whenever complex alterations of immune functions are observed.