Pulmonary renal syndrome in childhood: a report of twenty-one cases and a review of the literature

In adults, the term specific pulmonary renal syndrome describes disorders with pulmonary and glomerular manifestations and includes Wegener's granulomatosis, Goodpasture disease, and systemic lupus erythematosus. Nonspecific pulmonary renal syndrome refers to either pulmonary disease complicating glomerular disease, or glomerular diseases following pulmonary disease. Since little is known regarding pulmonary renal syndrome in childhood, we reviewed the charts of 21 pediatric patients with pulmonary renal syndromes treated by the Department of Pediatrics, University of Bern between 1991 and 1998; we also reviewed the pediatric literature that deals with specific pulmonary renal syndromes. Specific pulmonary renal syndrome was noted in 3 children with systemic vasculitis (Wegener granulomatosis, N = 2; microscopic polyangiitis, N = 1) and 2 with systemic lupus erythematosus. Nonspecific pulmonary renal syndrome was observed in 12 patients with pulmonary edema (N = 9), pulmonary thromboembolism (N = 2), and pulmonary infection (N = 1) complicating the course of a glomerular disease, and in 4 children with a pulmonary disease followed by a glomerular disease. Review of the literature disclosed 52 cases of specific pulmonary renal syndrome other than systemic lupus erythematosus: Wegener granulomatosis (N = 28), Goodpasture disease (N = 13), and Henoch-Schönlein purpura (N = 11). In addition, hemolytic uremic syndrome complicated pneumococcal pneumonia in 32 cases. We conclude that pulmonary renal syndromes need to be looked for in childhood. Apart from Wegener granulomatosis, Goodpasture disease, and systemic lupus erythematosus, Henoch-Schönlein purpura and hemolytic-uremic syndrome occasionally have both pulmonary and renal features.

An immunohistochemical procedure to detect patients with paraganglioma and phaeochromocytoma with germline SDHB, SDHC, or SDHD gene mutations: a retrospective and prospective analysis

BACKGROUND: Phaeochromocytomas and paragangliomas are neuro-endocrine tumours that occur sporadically and in several hereditary tumour syndromes, including the phaeochromocytoma-paraganglioma syndrome. This syndrome is caused by germline mutations in succinate dehydrogenase B (SDHB), C (SDHC), or D (SDHD) genes. Clinically, the phaeochromocytoma-paraganglioma syndrome is often unrecognised, although 10-30% of apparently sporadic phaeochromocytomas and paragangliomas harbour germline SDH-gene mutations. Despite these figures, the screening of phaeochromocytomas and paragangliomas for mutations in the SDH genes to detect phaeochromocytoma-paraganglioma syndrome is rarely done because of time and financial constraints. We investigated whether SDHB immunohistochemistry could effectively discriminate between SDH-related and non-SDH-related phaeochromocytomas and paragangliomas in large retrospective and prospective tumour series. METHODS: Immunohistochemistry for SDHB was done on 220 tumours. Two retrospective series of 175 phaeochromocytomas and paragangliomas with known germline mutation status for phaeochromocytoma-susceptibility or paraganglioma-susceptibility genes were investigated. Additionally, a prospective series of 45 phaeochromocytomas and paragangliomas was investigated for SDHB immunostaining followed by SDHB, SDHC, and SDHD mutation testing. FINDINGS: SDHB protein expression was absent in all 102 phaeochromocytomas and paragangliomas with an SDHB, SDHC, or SDHD mutation, but was present in all 65 paraganglionic tumours related to multiple endocrine neoplasia type 2, von Hippel-Lindau disease, and neurofibromatosis type 1. 47 (89%) of the 53 phaeochromocytomas and paragangliomas with no syndromic germline mutation showed SDHB expression. The sensitivity and specificity of the SDHB immunohistochemistry to detect the presence of an SDH mutation in the prospective series were 100% (95% CI 87-100) and 84% (60-97), respectively. INTERPRETATION: Phaeochromocytoma-paraganglioma syndrome can be diagnosed reliably by an immunohistochemical procedure. SDHB, SDHC, and SDHD germline mutation testing is indicated only in patients with SDHB-negative tumours. SDHB immunohistochemistry on phaeochromocytomas and paragangliomas could improve the diagnosis of phaeochromocytoma-paraganglioma syndrome. FUNDING: The Netherlands Organisation for Scientific Research, Dutch Cancer Society, Vanderes Foundation, Association pour la Recherche contre le Cancer, Institut National de la Santé et de la Recherche Médicale, and a PHRC grant COMETE 3 for the COMETE network.

Better conduct of clinical trials: the control group in critical care trials

OBJECTIVE: To review trial design issues related to control groups. DESIGN: Review of the literature with specific reference to critical care trials. MAIN RESULTS AND CONCLUSIONS: Performing randomized controlled trials in the critical care setting presents specific problems: studies include patients with rapidly lethal conditions, the majority of intensive care patients suffer from syndromes rather than from well-definable diseases, the severity of such syndromes cannot be precisely assessed, and the treatment consists of interacting therapies. Interactions between physiology, pathophysiology, and therapies are at best marginally understood and may have a major impact on study design and interpretation of results. Selection of the right control group is crucial for the interpretation and clinical implementation of results. Studies comparing new interventions with current ones or different levels of current treatments have the problem of the necessity of defining "usual care." Usual care controls without any constraints typically include substantial heterogeneity. Constraints in the usual therapy may help to reduce some variation. Inclusion of unrestricted usual care groups may help to enhance safety. Practice misalignment is a novel problem in which patients receive a treatment that is the direct opposite of usual care, and occurs when fixed-dose interventions are used in situations where care is normally titrated. Practice misalignment should be considered in the design and interpretation of studies on titrated therapies.

Asymmetric Effects of Loss and Gain of a Floral Trait on Pollinator Preference

Shifts in pollination syndromes involve coordinated changes in multiple floral traits. This raises the question of how plants can cope with rapid changes in pollinator availability by the slow process of accumulation of mutations in multiple genes. Here we study the transition from bee to hawkmoth pollination in the genus Petunia. Interspecific crosses followed by single locus introgressions were used to recreate putative intermediate evolutionary stages in the evolution of moth pollination. The effect of the loss/gain of petal color was asymmetric: it had no influence on the established pollinator but enhanced visitation by the new pollinator. Therefore, shifts in pollination syndromes may proceed through intermediate stages of reduced specialization and consequently enhanced reproductive assurance. The loss of petal color in moth-pollinated Petunia involves null mutations in a single regulatory gene, An2. Such simple genetic changes may be sufficiently rapid and frequent to ensure survival during pollinator failure.

Tight Genetic Linkage of Prezygotic Barrier Loci Creates a Multifunctional Speciation Island in Petunia

Most flowering plants depend on animal vectors for pollination and seed dispersal. Differential pollinator preferences lead to premating isolation and thus reduced gene flow between interbreeding plant populations [1, 2, 3 and 4]. Sets of floral traits, adapted to attract specific pollinator guilds, are called pollination syndromes [5]. Shifts in pollination syndromes have occurred surprisingly frequently [6], considering that they must involve coordinated changes in multiple genes affecting multiple floral traits. Although the identification of individual genes specifying single pollination syndrome traits is in progress in many species, little is known about the genetic architecture of coadapted pollination syndrome traits and how they are embedded within the genome [7]. Here we describe the tight genetic linkage of loci specifying five major pollination syndrome traits in the genus Petunia: visible color, UV absorption, floral scent production, pistil length, and stamen length. Comparison with other Solanaceae indicates that, in P. exserta and P. axillaris, loci specifying these floral traits have specifically become clustered into a multifunctional “speciation island” [ 8 and 9]. Such an arrangement promotes linkage disequilibrium and avoids the dissolution of pollination syndromes by recombination. We suggest that tight genetic linkage provides a mechanism for rapid switches between distinct pollination syndromes in response to changes in pollinator availabilities.

Color and Scent: How Single Genes Influence Pollinator Attraction

A major function of angiosperm flowers is the recruitment of animal pollinators that serve to transfer pollen among conspecific plants. Distinct sets of floral characteristics, called pollination syndromes, are correlated with visitation by specific groups of pollinators. Switches among pollination syndromes have occurred in many plant families. Such switches must have involved coordinated changes in multiple traits and multiple genes. Two well-studied floral traits affecting pollinator attraction are petal color and scent production. We review current knowledge about the biosynthetic pathways for floral color and scent production and their interaction at the genetic and biochemical levels. A key question in the field concerns the genes that underlie natural variation in color and scent and how such genes affect pollinator preference, reproductive isolation, and ultimately speciation.

Kaposi sarcoma-associated herpes virus and response to antiretroviral therapy: a prospective study of HIV-infected adults

BACKGROUND The possible impact of coinfection with the Kaposi sarcoma-associated herpes virus (KSHV) on the response to antiretroviral therapy (ART) is unknown. Prospective studies are rare, particularly in Africa. METHODS We enrolled a prospective cohort of HIV-infected adults initiating ART in Johannesburg, South Africa. The subjects were defined as seropositive to KSHV if they were reactive to either KSHV lytic K8.1 or latent Orf73 antigen or to both. The subjects were followed from ART initiation until 18 months of treatment. HIV viral load and CD4 counts were tested 6 monthly. Linear generalized estimating and log-binomial regression models were used to estimate the effect of KSHV infection on immunologic recovery and response and HIV viral load suppression within 18 months after ART initiation. RESULTS Three hundred eighty-five subjects initiating ART from November 2008 to March 2009 were considered to be eligible including 184 (48%) KSHV+. The KSHV+ group was similar to the KSHV- in terms of age, gender, initiating CD4 count, body mass index, tuberculosis, and hemoglobin levels. The KSHV+ group gained a similar number of cells at 6 [difference of 10 cells per cubic millimeter, 95% confidence interval (CI): -11 to 31], 12 (3 cells per cubic millimeter, 95% CI: -19 to 25), and 18 months (24 cells per cubic millimeter, 95% CI: -13 to 61) compared with that gained by the KSHV- group. Adjusted relative risk of failure to suppress viral load to <400 copies per milliliter (1.03; 95% CI: 0.90 to 1.17) were similar for KSHV+ and KSHV- by 6 months on treatment. CONCLUSIONS In a population with a high KSHV prevalence, HIV-positive adults coinfected with KSHV achieved similar immunologic and virologic responses to ART early after treatment initiation compared with those with KSHV-.

CD4 count slope and mortality in HIV-infected patients on antiretroviral therapy: multicohort analysis from South Africa

BACKGROUND In many resource-limited settings monitoring of combination antiretroviral therapy (cART) is based on the current CD4 count, with limited access to HIV RNA tests or laboratory diagnostics. We examined whether the CD4 count slope over 6 months could provide additional prognostic information. METHODS We analyzed data from a large multicohort study in South Africa, where HIV RNA is routinely monitored. Adult HIV-positive patients initiating cART between 2003 and 2010 were included. Mortality was analyzed in Cox models; CD4 count slope by HIV RNA level was assessed using linear mixed models. RESULTS About 44,829 patients (median age: 35 years, 58% female, median CD4 count at cART initiation: 116 cells/mm) were followed up for a median of 1.9 years, with 3706 deaths. Mean CD4 count slopes per week ranged from 1.4 [95% confidence interval (CI): 1.2 to 1.6] cells per cubic millimeter when HIV RNA was <400 copies per milliliter to -0.32 (95% CI: -0.47 to -0.18) cells per cubic millimeter with >100,000 copies per milliliter. The association of CD4 slope with mortality depended on current CD4 count: the adjusted hazard ratio (aHRs) comparing a >25% increase over 6 months with a >25% decrease was 0.68 (95% CI: 0.58 to 0.79) at <100 cells per cubic millimeter but 1.11 (95% CI: 0.78 to 1.58) at 201-350 cells per cubic millimeter. In contrast, the aHR for current CD4 count, comparing >350 with <100 cells per cubic millimeter, was 0.10 (95% CI: 0.05 to 0.20). CONCLUSIONS Absolute CD4 count remains a strong risk for mortality with a stable effect size over the first 4 years of cART. However, CD4 count slope and HIV RNA provide independently added to the model.

Facts and myths regarding the maxillary midline frenum and its treatment: a systematic review of the literature

OBJECTIVE To systematically review the current literature on the maxillary midline frenum and associated conditions and complications, as well as the recommended treatment options. METHOD AND MATERIALS A detailed MEDLINE database search was carried out to provide evidence about the epidemiology, associated pathologies, and treatment options regarding the maxillary frenum. Of the 206 initially identified articles, 48 met the inclusion criteria. RESULTS The maxillary frenum is highly associated with a number of syndromes and developmental abnormalities. A hypertrophic frenum may be involved in the etiology of the midline diastema. There is also a tendency by orthodontists to suggest posttreatment removal of the frenum (frenectomy). Studies on the cause of gingival recession due to the maxillary frenum are inconclusive. An injured frenum in combination with other traumas and doubtful history might point to child abuse. The involvement of hyperplastic frena in the pathogenesis of peri-implant diseases remains uncertain. There seems to be a clinical interest regarding lasers for surgery for treatment of maxillary frena. The superiority of laser treatment in relation to conventional surgical methods has not yet been demonstrated in the literature. CONCLUSION A maxillary frenum is a clinical symptom in numerous syndromic conditions and plays a role in the development of the median midline diastema. Nevertheless, the contribution to gingival recession and peri-implant diseases in the region of the maxillary incisors is rather controversial. Laser techniques are reported as the method of choice for the surgical removal of frena; however, this needs to be substantiated by appropriate prospective controlled studies.

Tracing of patients lost to follow-up and HIV transmission: Mathematical modelling study based on two large ART programmes in Malawi

OBJECTIVES: Treatment as prevention depends on retaining HIV-infected patients in care. We investigated the effect on HIV transmission of bringing patients lost to follow up (LTFU) back into care. DESIGN: Mathematical model. METHODS: Stochastic mathematical model of cohorts of 1000 HIV-infected patients on antiretroviral therapy (ART), based on data from two clinics in Lilongwe, Malawi. We calculated cohort viral load (CVL; sum of individual mean viral loads each year) and used a mathematical relationship between viral load and transmission probability to estimate the number of new HIV infections. We simulated four scenarios: 'no LTFU' (all patients stay in care); 'no tracing' (patients LTFU are not traced); 'immediate tracing' (after missed clinic appointment); and, 'delayed tracing' (after six months). RESULTS: About 440 of 1000 patients were LTFU over five years. CVL (million copies/ml per 1000 patients) were 3.7 (95% prediction interval [PrI] 2.9-4.9) for no LTFU, 8.6 (95% PrI 7.3-10.0) for no tracing, 7.7 (95% PrI 6.2-9.1) for immediate, and 8.0 (95% PrI 6.7-9.5) for delayed tracing. Comparing no LTFU with no tracing the number of new infections increased from 33 (95% PrI 29-38) to 54 (95% PrI 47-60) per 1000 patients. Immediate tracing prevented 3.6 (95% PrI -3.3-12.8) and delayed tracing 2.5 (95% PrI -5.8-11.1) new infections per 1000. Immediate tracing was more efficient than delayed tracing: 116 and to 142 tracing efforts, respectively, were needed to prevent one new infection. CONCLUSION: Tracing of patients LTFU enhances the preventive effect of ART, but the number of transmissions prevented is small.

Differential effects of captopril and nitrates on muscle sympathetic nerve activity in volunteers

BACKGROUND The sympathetic nervous system (SNS) is an important regulator of cardiovascular function. Activation of SNS plays an important role in the pathophysiology and the prognosis of cardiovascular diseases such as heart failure, acute coronary syndromes, arrhythmia, and possibly hypertension. Vasodilators such as adenosine and sodium nitroprusside are known to activate SNS via baroreflex mechanisms. Because vasodilators are widely used in the treatment of patients with cardiovascular diseases, the aim of the present study was to assess the influence of clinically used dosages of isosorbide dinitrate and captopril on sympathetic nerve activity at rest and during stimulatory maneuvers. METHODS AND RESULTS Twenty-eight healthy volunteers were included in this double-blind placebo-controlled study, and muscle sympathetic nerve activity (MSA; with microelectrodes in the peroneal nerve), blood pressure, heart rate, and neurohumoral parameters were measured before and 90 minutes after the oral administration of 40 mg isosorbide dinitrate or 6.25 mg captopril. Furthermore, a 3-minute mental stress test and a cold pressor test were performed before and 90 minutes after drug administration. Resting MSA did not change after captopril and decreased compared with placebo (P < .05 versus placebo), whereas isosorbide dinitrate led to a marked increase in MSA (P < .05). Systolic blood pressure was reduced by isosorbide dinitrate (P < .05), whereas captopril decreased diastolic blood pressure (P < .05). The increases in MSA, blood pressure, and heart rate during mental stress were comparable before and after drug administration regardless of the medication. During cold pressor test, MSA and systolic and diastolic blood pressures increased to the same degree independent of treatment, but after isosorbide dinitrate, the increase in MSA seemed to be less pronounced. Heart rate did not change during cold stimulation. Plasma renin activity increased after captopril and isosorbide dinitrate (P < .05), whereas placebo had no effect. Endothelin-1 increased after placebo and isosorbide dinitrate (P < .05) but not after captopril. CONCLUSIONS Thus, captopril suppressed MSA despite lowering of diastolic blood pressure but allowed normal adaptation of the SNS during mental or physical stress. In contrast, the nitrate strongly activated the SNS under baseline conditions. These findings demonstrate that vasodilators differentially interact with the SNS, which could be of importance in therapeutic strategies for the treatment of patients with cardiovascular diseases.

Impact of recommendation updates in well-controlled patients on nonrecommended antiretroviral therapies: the Swiss HIV cohort study

BACKGROUND HIV treatment recommendations are updated as clinical trials are published. Whether recommendations drive clinicians to change antiretroviral therapy in well-controlled patients is unexplored. METHODS We selected patients with undetectable viral loads (VLs) on nonrecommended regimens containing double-boosted protease inhibitors (DBPIs), triple-nucleoside reverse transcriptase inhibitors (NRTIs), or didanosine (ddI) plus stavudine (d4T) at publication of the 2006 International AIDS Society recommendations. We compared demographic and clinical characteristics with those of control patients with undetectable VL not on these regimens and examined clinical outcome and reasons for treatment modification. RESULTS At inclusion, 104 patients were in the DBPI group, 436 in the triple-NRTI group, and 19 in the ddI/d4T group. By 2010, 28 (29%), 204 (52%), and 1 (5%) patient were still on DBPIs, triple-NRTIs, and ddI plus d4T, respectively. 'Physician decision,' excluding toxicity/virological failure, drove 30% of treatment changes. Predictors of recommendation nonobservance included female sex [adjusted odds ratio (aOR) 2.69, 95% confidence interval (CI) 1 to 7.26; P = 0.01] for DPBIs, and undetectable VL (aOR 3.53, 95% CI 1.6 to 7.8; P = 0.002) and lack of cardiovascular events (aOR 2.93, 95% CI 1.23 to 6.97; P = 0.02) for triple-NRTIs. All patients on DBPIs with documented diabetes or a cardiovascular event changed treatment. Recommendation observance resulted in lower cholesterol values in the DBPI group (P = 0.06), and more patients having undetectable VL (P = 0.02) in the triple-NRTI group. CONCLUSION The physician's decision is the main factor driving change from nonrecommended to recommended regimens, whereas virological suppression is associated with not switching. Positive clinical outcomes observed postswitch underline the importance of observing recommendations, even in well-controlled patients.

Do childhood cancer survivors with physical performance limitations reach healthy activity levels?

BACKGROUND The extent to which physical performance limitations affect the ability of childhood cancer survivors to reach healthy activity levels is unknown. Therefore this study aims to describe the effect of different types of limitations on activity levels in survivors. PROCEDURE Within the Swiss Childhood Cancer Survivor Study we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. We measured healthy activity levels using international guidelines and assessed different kinds of performance limitations (visual impairment, weight and endurance problems, cardiorespiratory, musculoskeletal, and neurological problems, pain and fatigue syndromes). RESULTS The sample included 1,560 survivors (75% response rate), of whom 209 (13.5%) reported they have performance limitations. Forty-two percent of survivors with limitations reached healthy activity levels, compared to 57% of survivors without limitations. Least active were survivors with vision impairments (25% active), weight and endurance problems (27.3%), cardiorespiratory problems (36.4%), and musculoskeletal problems (43.1%). After adjusting for socio-demographic variables and type of cancer, we found that survivors with limitations were 1.4 (95%CI 1.0-2.0; P = 0.047) times more likely to be inactive. CONCLUSIONS Although many survivors with physical performance limitations maintain healthy activity levels, there is room for improvement. Adapted and targeted physical activity counseling for survivors with performance limitations might help them to raise level of activity and pursue a healthy lifestyle.

Immune recovery after starting ART in HIV-infected patients presenting and not presenting with tuberculosis in South Africa

We studied the immune response after starting antiretroviral treatment (ART) in 15,646 HIV-infected patients with or without tuberculosis (TB) at presentation in 3 ART programs in South Africa between 2003 and 2010. Patients presenting with TB had similar increases in CD4 cells compared with all other patients (adjusted difference 4.9 cells/µL per 6 months, 95% confidence interval: 0.2 to 9.7). Younger age, advanced clinical stage, female sex, and lower CD4 cell count at ART start were all associated with steeper CD4 slopes. In South Africa, HIV-infected patients presenting with TB experience immune recovery after starting ART that is no worse than in other patients.

The prevalence of widespread central hypersensitivity in chronic pain patients

BACKGROUND Chronic pain is associated with generalized hypersensitivity and impaired endogenous pain modulation (conditioned pain modulation; CPM). Despite extensive research, their prevalence in chronic pain patients is unknown. This study investigated the prevalence and potential determinants of widespread central hypersensitivity and described the distribution of CPM in chronic pain patients. METHODS We examined 464 consecutive chronic pain patients for generalized hypersensitivity and CPM using pressure algometry at the second toe and cold pressor test. Potential determinants of generalized central hypersensitivity were studied using uni- and multivariate regression analyses. Prevalence of generalized central hypersensitivity was calculated for the 5th, 10th and 25th percentile of normative values for pressure algometry obtained by a previous large study on healthy volunteers. CPM was addressed on a descriptive basis, since normative values are not available. RESULTS Depending on the percentile of normative values considered, generalized central hypersensitivity affected 17.5-35.3% of patients. 23.7% of patients showed no increase in pressure pain threshold after cold pressor test. Generalized central hypersensitivity was more frequent and CPM less effective in women than in men. Unclearly classifiable pain syndromes showed higher frequencies of generalized central hypersensitivity than other pain syndromes. CONCLUSIONS Although prevalent in chronic pain, generalized central hypersensitivity is not present in every patient. An individual assessment is therefore required in order to detect altered pain processing. The broad basic knowledge about central hypersensitivity now needs to be translated into concrete clinical consequences, so that patients can be offered an individually tailored mechanism-based treatment.