Post-streptococcal glomerulonephritis is a strong risk factor for chronic kidney disease in later life

Efficacy and Pharmacokinetics Evaluation of a Single Oral Dose of Afoxolaner against Sarcoptes scabiei in the Porcine Scabies Model for Human Infestation

Scabies is a major and potentially growing public health problem worldwide with an unmet need for acaricidal agents with greater efficacy and improved pharmacological properties for its treatment. The objective of the present study was to assess the efficacy and describe the pharmacokinetics profile of a novel acaricide, afoxolaner (AFX), in a relevant experimental porcine model. Twelve pigs were experimentally infested and either treated with 2.5 mg/kg single dose oral AFX (n = 4) or 0.2 mg/kg, two doses 8 days apart, oral ivermectin ([IVM] n = 4) or not treated for scabies (n = 4). The response to treatment was assessed by the reduction of mite counts in skin scrapings as well as clinical and pruritus scores over time. Plasma and skin pharmacokinetics profiles for both AFX and IVM were evaluated. AFX efficacy was 100% at days 8 and 14 posttreatment and remained unchanged until the study end (day 45). IVM efficacy was 86% and 97% on days 8 and 14, respectively, with a few mites recovered at the study end. Clinical and pruritus scores decreased in both treated groups and remained constant in the control group. Plasma mean residence times (MRT) were 7.1 ± 2.4 and 1.1 ± 0.2 days for AFX and IVM, respectively. Skin MRT values were 16.2 ± 16.9 and 2.7 ± 0.5 days for AFX and IVM, respectively. Overall, a single oral dose of AFX was efficacious for the treatment of scabies in experimentally infested pigs and showed remarkably long MRTs in plasma and, notably, in the skin.

Differential prevalence of hematuria and proteinuria with socio-demographic factors among school children in Hualien, Taiwan

BACKGROUND

Pediatric hematuria/proteinuria is a risk factor for chronic kidney disease in later life, and school urinary screening can detect asymptomatic glomerulonephritis in the early stage. This study aimed to evaluate the prevalence of hematuria/proteinuria and its association with different socio-demographic factors among school children in 2013 in Hualien, Taiwan.

METHODS

A cross-sectional study was conducted among first, fourth, and seventh graders. Health examination results and urinalysis data were analyzed. Logistic regression models were used to the simultaneously analyze the association between the prevalence of hematuria/proteinuria and socio-demographic factors.

RESULTS

A total of 9544 students were included. The overall prevalence of hematuria and proteinuria was 4.1% and 5.7%, respectively. Students who were females, of a high grade level, of aboriginal ethnicity, and living in rural areas had higher hematuria risk (all P < 0.001) than other students. Underweight students had low odds ratio (0.53) of hematuria (P < 0.001). Seventh-grade students had higher odds ratio (3.63) of proteinuria than first grade students (P < 0.001). Students with both parents of aboriginal descent had lower odds ratio (0.81) of proteinuria than those with non-aboriginal parents (P = 0.044). Only higher grade level students had significantly higher risk of combined hematuria and light proteinuria (odds ratio: 10.67) and heavy proteinuria with/without hematuria (odds ratio: 3.22) than first graders.

CONCLUSION

Increased hematuria/proteinuria prevalence was noted in our county as compared to prior studies. Hematuria/proteinuria was significantly associated with gender, grade level, body mass index, ethnicity, and residence urbanization. Our data can be used for future longitudinal dataset collection to prevent pediatric renal disorders in Taiwan.

Pediatric post-streptococcal glomerulonephritis: Clinical and laboratory data

BACKGROUND

Acute post-streptococcal glomerulonephritis (APSGN) is the most common post-infectious glomerulonephritis in childhood. The aim of this study was therefore to identify the possible risk factor(s) responsible for decreased glomerular filtration rate (GFR) in APSGN.

METHODS

The data of patients followed up with a diagnosis of APSGN in the Pediatric Nephrology Clinic of Gaziantep University Hospital between October 2014 and October 2016 were retrospectively evaluated.

RESULTS

The total number of subjects was 75 (male/female, 42/33) with a mean age of 8.20 ± 3.25 years. The most common presentations were edema (86.7%), macroscopic hematuria (82.7%) and hypertension (73.3%, n = 55). On laboratory examination, 28 children (37.3%) had hypoalbuminemia, 58 (77.3%) had proteinuria, 20 (26.7%) had increased C-reactive protein (CRP), while 74 (98.7%) and 12 (16%) had decreased complement (C)3 and C4, respectively. The number of children with GFR <90 mL/min/1.73 m² was 22 (29.3%). The risk of decreased GFR was significantly higher in patients with increased CRP (P = 0.001; OR, 3.58), hypoalbuminemia (P = 0.006; OR, 4.83), and decreased C4 (P = 0.010; OR, 11.53). Additionally, white blood cell (WBC) count, neutrophil count, and neutrophil/lymphocyte ratio (NLR) were significantly higher (P = 0.02, P = 0.006, P = 0.004, respectively) in patients with low GFR.

CONCLUSIONS

Although the prognosis of APSGN in children is good, severe systemic complications and renal failure may develop during the follow-up period. Decreased C4, presence of hypoalbuminemia, and increased inflammatory markers (WBC, CRP, neutrophil count and NLR) might be possible risk factors for severity of renal involvement. Decreased C4, in particular, may be a risk factor for decreased GFR in those children.

Ivermectin and permethrin for treating scabies

BACKGROUND

Scabies is an intensely itchy parasitic infection of the skin. It occurs worldwide, but is particularly problematic in areas of poor sanitation, overcrowding, and social disruption. In recent years, permethrin and ivermectin have become the most relevant treatment options for scabies.

OBJECTIVES

To assess the efficacy and safety of topical permethrin and topical or systemic ivermectin for scabies in people of all ages.

SEARCH METHODS

We searched the following databases up to 25 April 2017: the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, Embase, LILACS, and IndMED. We searched the World Health Organization International Clinical Trials Registry Platform, the ISRCTN registry, CenterWatch Clinical Trials Listing, ClinicalTrials.gov, TrialsCentral, and the UK Department of Health National Research Register for ongoing trials. We also searched multiple sources for grey literature and checked reference lists of included studies for additional trials.

SELECTION CRITERIA

We included randomized controlled trials that compared permethrin or ivermectin against each other for people with scabies of all ages and either sex.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the identified records, extracted data, and assessed the risk of bias for the included trials.The primary outcome was complete clearance of scabies. Secondary outcomes were number of participants re-treated, number of participants with at least one adverse event, and number of participants withdrawn from study due to an adverse event.We summarized dichotomous outcomes using risk ratios (RR) with 95% confidence intervals (CI). If it was not possible to calculate the point estimate, we described the data qualitatively. Where appropriate, we calculated combined effect estimates using a random-effects model and assessed heterogeneity. We calculated numbers needed to treat for an additional beneficial outcome when we found a difference.We assessed the certainty of the evidence using the GRADE approach. We used the control rate average to provide illustrative clearance rates in the comparison groups.

MAIN RESULTS

Fifteen studies (1896 participants) comparing topical permethrin, systemic ivermectin, or topical ivermectin met the inclusion criteria. Overall, the risk of bias in the included trials was moderate: reporting in many studies was poor. Nearly all studies were conducted in South Asia or North Africa, where the disease is more common, and is associated with poverty.EfficacyOral ivermectin (at a standard dose of 200 μg/kg) may lead to slightly lower rates of complete clearance after one week compared to permethrin 5% cream. Using the average clearance rate of 65% in the trials with permethrin, the illustrative clearance with ivermectin is 43% (RR 0.65, 95% CI 0.54 to 0.78; 613 participants, 6 studies; low-certainty evidence). However, by week two there may be little or no difference (illustrative clearance of permethrin 74% compared to ivermectin 68%; RR 0.91, 95% CI 0.76 to 1.08; 459 participants, 5 studies; low-certainty evidence). Treatments with one to three doses of ivermectin or one to three applications of permethrin may lead to little or no difference in rates of complete clearance after four weeks' follow-up (illustrative cures with 1 to 3 applications of permethrin 93% and with 1 to 3 doses of ivermectin 86%; RR 0.92, 95% CI 0.82 to 1.03; 581 participants, 5 studies; low-certainty evidence).After one week of treatment with oral ivermectin at a standard dose of 200 μg/kg or one application of permethrin 5% lotion, there is probably little or no difference in complete clearance rates (illustrative cure rates: permethrin 73%, ivermectin 68%; RR 0.93, 95% CI 0.74 to 1.17; 120 participants, 1 study; moderate-certainty evidence). After two weeks of treatment, one dose of systemic ivermectin compared to one application of permethrin lotion may lead to similar complete clearance rates (extrapolated cure rates: 67% in both groups; RR 1.00, 95% CI 0.78 to 1.29; 120 participants, 1 study; low-certainty evidence).There is probably little or no difference in rates of complete clearance between systemic ivermectin at standard dose and topical ivermectin 1% lotion four weeks after initiation of treatment (illustrative cure rates: oral ivermectin 97%, ivermectin lotion 96%; RR 0.99, 95% CI 0.95 to 1.03; 272 participants, 2 studies; moderate-certainty evidence). Likewise, after four weeks, ivermectin lotion probably leads to little or no difference in rates of complete clearance when compared to permethrin cream (extrapolated cure rates: permethrin cream 94%, ivermectin lotion 96%; RR 1.02, 95% CI 0.96 to 1.08; 210 participants, 1 study; moderate-certainty evidence), and there is little or no difference among systemic ivermectin in different doses (extrapolated cure rates: 2 doses 90%, 1 dose 87%; RR 0.97, 95% CI 0.83 to 1.14; 80 participants, 1 study; high-certainty evidence).SafetyReporting of adverse events in the included studies was suboptimal. No withdrawals due to adverse events occurred in either the systemic ivermectin or the permethrin group (moderate-certainty evidence). Two weeks after treatment initiation, there is probably little or no difference in the proportion of participants treated with systemic ivermectin or permethrin cream who experienced at least one adverse event (55 participants, 1 study; moderate-certainty evidence). After four weeks, ivermectin may lead to a slightly larger proportion of participants with at least one adverse event (extrapolated rates: permethrin 4%, ivermectin 5%; RR 1.30, 95% CI 0.35 to 4.83; 502 participants, 4 studies; low-certainty evidence).Adverse events in participants treated with topical ivermectin were rare and of mild intensity and comparable to those with systemic ivermectin. For this comparison, it is uncertain whether there is any difference in the number of participants with at least one adverse event (very low-certainty evidence). No withdrawals due to adverse events occurred (62 participants, 1 study; moderate-certainty evidence).It is uncertain whether topical ivermectin or permethrin differ in the number of participants with at least one adverse event (very low-certainty evidence). We found no studies comparing systemic ivermectin in different doses that assessed safety outcomes.

AUTHORS' CONCLUSIONS

We found that for the most part, there was no difference detected in the efficacy of permethrin compared to systemic or topical ivermectin. Overall, few and mild adverse events were reported. Our confidence in the effect estimates was mostly low to moderate. Poor reporting is a major limitation.

More bark than bite: Comparative studies are needed to determine the importance of canine zoonoses in Aboriginal communities. A critical review of published research

The objective of this review was to identify and critique over forty years of peer-reviewed literature concerned with the transmission of canine zoonoses to Aboriginal people and determine the zoonotic organisms documented in dogs in Australian Aboriginal communities. A systematic literature search of public health, medical and veterinary databases identified 19 articles suitable for critical appraisal. Thirteen articles documented the occurrence of recognized zoonotic organisms in dogs in Aboriginal communities, including Toxocara canis, Dirofilaria immitis, Streptococcus dysgalactiae, Rickettsia felis, Sarcoptes scabiei and Giardia. Currently, there is definitive evidence indicating that dogs act as a reservoir for human scabies in Aboriginal communities. However, there is a need for large-scale, high-quality, comparative studies of dogs and humans from the same household to assess the occurrence and importance of transmission of S. scabiei and other diseases between dogs and humans. These studies should use current genetic and molecular techniques along with traditional techniques to identify and type organisms in order to better understand their epidemiology. This review has revealed that there is a lack of high-quality comparative studies to determine whether dogs are contributing to human disease by transmitting zoonoses. Our recommendations differ significantly from current public health policy and may have substantial implications for human and dog health.

Analysis of clinical presentation, pathological spectra, treatment and outcomes of biopsy-proven acute postinfectious glomerulonephritis in adult indigenous people of the Northern Territory of Australia

AIM

Acute postinfectious glomerulonephritis is common in indigenous communities in the Northern Territory, Australia. It is a major risk factor for the high prevalence of chronic kidney disease. We aimed to analyse the clinical presentation, pathological spectra, treatment and outcomes of biopsy-proven acute postinfectious glomerulonephritis in the Northern Territory.

METHODS

We performed a retrospective cohort analysis of all adult patients (≥18 years) who were diagnosed with acute postinfectious glomerulonephritis on native renal biopsies from 01/01/2004 to 31/05/2014. The outcome measure was end-stage renal disease requiring long-term dialysis.

RESULTS

Forty-three of 340 patients who had renal biopsies had acute postinfectious glomerulonephritis. Most were Aboriginals (88.4%). They had co-morbidities; diabetes mellitus (60.5%), hypertension (60.5%) and smoking (56.4%). Forty-nine per cent had multiple pathologies on biopsy. Predominant histological pattern was diffuse proliferative glomerulonephritis (72%). Main sites of infections were skin (47.6%) and upper respiratory tract infection (26.2%) with streptococcus and staphylococcus as predominant organisms. Fifty per cent of patients developed end-stage renal disease. On multivariable logistic regression analysis, those on dialysis had higher baseline creatinine (P = 0.003), higher albumin/creatinine ratio at presentation (P = 0.023), higher serum creatinine at presentation (P = 0.02) and lower estimated glomerular filtration rate at presentation (P = 0.012).

CONCLUSION

Overall, most patients had pre-existing pathology with superimposed acute postinfectious glomerulonephritis that led to poor outcomes in our cohort.

Global kidney health 2017 and beyond: a roadmap for closing gaps in care, research, and policy

The global nephrology community recognises the need for a cohesive plan to address the problem of chronic kidney disease (CKD). In July, 2016, the International Society of Nephrology hosted a CKD summit of more than 85 people with diverse expertise and professional backgrounds from around the globe. The purpose was to identify and prioritise key activities for the next 5-10 years in the domains of clinical care, research, and advocacy and to create an action plan and performance framework based on ten themes: strengthen CKD surveillance; tackle major risk factors for CKD; reduce acute kidney injury-a special risk factor for CKD; enhance understanding of the genetic causes of CKD; establish better diagnostic methods in CKD; improve understanding of the natural course of CKD; assess and implement established treatment options in patients with CKD; improve management of symptoms and complications of CKD; develop novel therapeutic interventions to slow CKD progression and reduce CKD complications; and increase the quantity and quality of clinical trials in CKD. Each group produced a prioritised list of goals, activities, and a set of key deliverable objectives for each of the themes. The intended users of this action plan are clinicians, patients, scientists, industry partners, governments, and advocacy organisations. Implementation of this integrated comprehensive plan will benefit people who are at risk for or affected by CKD worldwide.

Reducing major risk factors for chronic kidney disease

Chronic kidney disease (CKD) is a global public health concern and a key determinant of poor health outcomes. While the burden of CKD is reasonably well defined in developed countries, increasing evidence indicates that the CKD burden may be even greater in developing countries. Diabetes, hypertension, and obesity are major contributors to the global burden of the disease and are important traditional CKD risk factors; however, nontraditional CKD risk factors such as nephrotoxin exposure, kidney stones, fetal and maternal factors, infections, environmental factors, and acute kidney injury are also increasingly being recognized as major threats to global kidney health. A broad approach to CKD prevention begins with the identification of CKD risk factors in the population, followed by the development of appropriate mitigation strategies. Effective prevention policies rely on an accurate understanding of the incidence and prevalence of CKD in a given setting, as well as the distribution and burden of risk factors. Populations or individuals at CKD risk must be screened and treated early to prevent the onset of and delay the progression of the kidney disease. Systematically collected data should be analyzed at country, province, and district levels to identify regional disparities and CKD hotspots and develop targeted prevention strategies. Race-ethnicity, genetics, sex, socioeconomic status, and geography are likely modifiers of CKD risk. A comprehensive, informed approach to prevention that takes into account all of these factors is therefore required to successfully tackle the global CKD epidemic.

Host immune responses to the itch mite, Sarcoptes scabiei, in humans

Scabies is a parasitic disease due to infestation of skin by the burrowing mite Sarcoptes scabiei. Scabies is a major public health problem and endemic in resource poor communities worldwide affecting over 100 million people. Associated bacterial infections cause substantial morbidity, and in severe cases can lead to renal and cardiac diseases. Mite infestation of the skin causes localised cutaneous inflammation, pruritus, skin lesions, and allergic and inflammatory responses are mounted by the host against the mite and its products. Our current understanding of the immune and inflammatory responses associated with the clinical manifestations in scabies is far outweighed by the significant global impact of the disease. This review aims to provide a better understanding of human immune responses to S. scabiei in ordinary and crusted scabies phenotypes.

Beginning the trajectory to ESKD in adult life: albuminuria in Australian aboriginal children and adolescents

BACKGROUND

Globally, disadvantaged populations suffer a high burden of chronic kidney disease (CKD). The trajectory to CKD during childhood and adolescence remains unclear due to a paucity of longitudinal studies.

METHODS

This was a prospective, population-based cohort study in which since 2002 we have followed 3418 children (1469 non-Aboriginal and 1949 Aboriginal) attending participating schools across New South Wales (NSW), Australia. The albumin:creatinine ratio was measured by dipstick every 2 years together with the body mass index (BMI) and blood pressure. We used multivariable logistic generalised estimating equation models to examine whether Aboriginal children had a higher prevalence of albuminuria compared with non-Aboriginal children with increasing age and to identify potential risk factors.

RESULTS

The mean age at enrolment was 10.6 years, at which time 14.2 % of the children were obese and 16.0 % overweight, with 11.5 % found to have albuminuria. Over 8 years (11,387 participant-years) of follow-up the prevalence of albuminuria increased to 18.5 %, overweight to 16.1 % and obesity to 17.2 %. The BMI standard deviation score (SDS) was found to have a differential effect on the risk of albuminuria in Aboriginal and non-Aboriginal children (P interaction < 0.01). The prevalence of albuminuria decreased as the BMI SDS increased in both groups of children, but it increased more in non-Aboriginal children, leading to a 2.5 % higher prevalence of albuminuria in overweight Aboriginal children (95 % confidence interval 1.0-4.2 %).

CONCLUSION

Compared with non-Aboriginal children, Aboriginal children are of higher risk of albuminuria when overweight or obese. We hypothesise that overweight and obesity are key contributors to the development of adult onset CKD among Aboriginal Australians, which needs further exploration in future studies.

Familial aggregation of albuminuria and arterial hypertension in an Aboriginal Australian community and the contribution of variants in ACE and TP53

Background

Aboriginal Australians are at high risk of cardiovascular, metabolic and renal diseases, resulting in a marked reduction in life expectancy when compared to the rest of the Australian population. This is partly due to recognized environmental and lifestyle risk factors, but a contribution of genetic susceptibility is also likely.

Methods

Using results from a comprehensive survey of one community (N = 1350 examined individuals), we have tested for familial aggregation of plasma glucose, arterial blood pressure, albuminuria (measured as urinary albumin to creatinine ratio, UACR) and estimated glomerular filtration rate (eGFR), and quantified the contribution of variation at four candidate genes (ACE; TP53; ENOS3; MTHFR).

Results

In the subsample of 357 individuals with complete genotype and phenotype data we showed that both UACR (h² = 64%) and blood pressure (sBP h² = 29%, dBP, h² = 11%) were significantly heritable. The ACE insertion-deletion (P = 0.0009) and TP53 codon72 polymorphisms (P = 0.003) together contributed approximately 15% of the total heritability of UACR, with an effect of ACE genotype on BP also clearly evident.

Conclusions

While the effects of the ACE insertion-deletion on risk of renal disease (especially in the setting of diabetes) are well recognized, this is only the second study to implicate p53 genotype as a risk factor for albuminuria - the other being an earlier study we performed in a different Aboriginal community (McDonald et al., J Am Soc Nephrol 13: 677-83, 2002). We conclude that there are significant genetic contributions to the high prevalence of chronic diseases observed in this population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0396-2) contains supplementary material, which is available to authorized users.

Protocol for the systematic review of the prevention, treatment and public health management of impetigo, scabies and fungal skin infections in resource-limited settings

BACKGROUND

Impetigo, scabies, and fungal skin infections disproportionately affect populations in resource-limited settings. Evidence for standard treatment of skin infections predominantly stem from hospital-based studies in high-income countries. The evidence for treatment in resource-limited settings is less clear, as studies in these populations may lack randomisation and control groups for cultural, ethical or economic reasons. Likewise, a synthesis of the evidence for public health control within endemic populations is also lacking. We propose a systematic review of the evidence for the prevention, treatment and public health management of skin infections in resource-limited settings, to inform the development of guidelines for the standardised and streamlined clinical and public health management of skin infections in endemic populations.

METHODS

The protocol has been designed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols statement. All trial designs and analytical observational study designs will be eligible for inclusion. A systematic search of the peer-reviewed literature will include PubMed, Excertpa Medica and Global Health. Grey literature databases will also be systematically searched, and clinical trials registries scanned for future relevant studies. The primary outcome of interest will be the clinical cure or decrease in prevalence of impetigo, scabies, crusted scabies, tinea capitis, tinea corporis or tinea unguium. Two independent reviewers will perform eligibility assessment and data extraction using standardised electronic forms. Risk of bias assessment will be undertaken by two independent reviewers according to the Cochrane Risk of Bias tool. Data will be tabulated and narratively synthesised. We expect there will be insufficient data to conduct meta-analysis. The final body of evidence will be reported against the Grades of Recommendation, Assessment, Development and Evaluation grading system.

DISCUSSION

The evidence derived from the systematic review will be used to inform the development of guidelines for the management of skin infections in resource-limited settings. The evidence derived will be intended for use by clinicians, public health practitioners and policy makers in the treatment of skin infections and the development of skin infection control programmes. The review will identify any gaps in the current evidence to provide direction for future research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015029453.

Whole genome sequencing reveals extensive community-level transmission of group A Streptococcus in remote communities

Impetigo is common in remote Indigenous children of northern Australia, with the primary driver in this context being Streptococcus pyogenes [or group A Streptococcus (GAS)]. To reduce the high burden of impetigo, the transmission dynamics of GAS must be more clearly elucidated. We performed whole genome sequencing on 31 GAS isolates collected in a single community from children in 11 households with ⩾2 GAS-infected children. We aimed to determine whether transmission was occurring principally within households or across the community. The 31 isolates were represented by nine multilocus sequence types and isolates within each sequence type differed from one another by only 0-3 single nucleotide polymorphisms. There was evidence of extensive transmission both within households and across the community. Our findings suggest that strategies to reduce the burden of impetigo in this setting will need to extend beyond individual households, and incorporate multi-faceted, community-wide approaches.

The Prevalence of Scabies and Impetigo in the Solomon Islands: A Population-Based Survey

Background

Scabies and impetigo are common, important and treatable skin conditions. Reports from several Pacific island countries show extremely high prevalence of these two conditions, but for many countries, including the Solomon Islands, there is a paucity of epidemiological data.

Methodology

Ten rural villages in the Western Province of the Solomon Islands were included in the study, chosen so that data collection could be integrated with an existing project investigating clinical and serological markers of yaws. All residents were eligible to participate, and 1908 people were enrolled. Participants were interviewed and examined by a paediatric registrar, who recorded relevant demographic information, and made a clinical diagnosis of scabies and/or impetigo, severity and distribution.

Principal Findings

The total unweighted prevalence of scabies was 19.2% (95% confidence interval [CI] 17.5–21.0), and age and gender weighted prevalence 19.2% (95%CI 16.7–21.9). The adult prevalence of scabies was 10.4% (95%CI 8.2–13.2), and the highest prevalence was found in infants < 1 year of age (34.1%, adjusted odds ratio [AOR] compared with adults: 3.6, 95%CI 2.2–6.0) and children aged 1–4 years (25.7%, AOR 2.6, 95%CI 1.7–3.9). Scabies affected two or more body regions in 80.9% of participants, and 4.4% of scabies cases were classified as severe. The total unweighted prevalence of active impetigo was 32.7% (95%CI 30.6–34.8), and age and gender weighted prevalence 26.7% (95%CI 24.2–29.5). The highest prevalence was found in children aged 1–4 years (42.6%, AOR compared with adults: 4.1, 95%CI 2.9–5.8). Scabies infestation was associated with active impetigo infection (AOR 2.0, 95%CI 1.6–2.6); with 41.1% of active impetigo cases also having scabies.

Conclusions and Significance

Scabies and impetigo are very common in the rural Western Province of the Solomon Islands. Scabies infestation is strongly associated with impetigo. Community control strategies for scabies may reduce the burden of both conditions and their downstream complications.

Scabies, a parasitic infection, and impetigo, a superficial bacterial infection, are treatable skin conditions found most commonly in resource-limited settings. Scabies is strongly associated with impetigo. Complications of impetigo include sepsis and invasive infections, and post-infective complications such as acute post streptococcal glomerulonephritis and acute rheumatic fever. Good data on scabies and impetigo prevalence are lacking for most countries, but existing evidence suggests the Pacific region has among the highest prevalence of these conditions in the world. Our study aimed to establish the prevalence of scabies and impetigo in the Western Province of the Solomon Islands, a South Pacific nation made up of over 900 islands and over 500,000 inhabitants. We assessed over 1900 people of all ages, and found a very high burden of skin infections, with scabies affecting one in five people, and active impetigo in one in three. Infants and children were affected more than adults. Scabies infestation was strongly associated with impetigo, supporting the hypothesis that community control strategies for scabies may be successful in reducing the burden of impetigo and its sequelae.

Impetigo and scabies - Disease burden and modern treatment strategies

Impetigo and scabies both present different challenges in resource-limited compared with industrialised settings. Severe complications of these skin infections are common in resource-limited settings, where the burden of disease is highest. The microbiology, risk factors for disease, diagnostic approaches and availability and suitability of therapies also vary according to setting. Taking this into account we aim to summarise recent data on the epidemiology of impetigo and scabies and describe the current evidence around approaches to individual and community based treatment.

Small vessel microembolization and acute glomerulonephritis following infection of aesthetic filler implants

Background

The systemic consequences of esthetic filler injections are poorly understood.

Case presentation

We report a patient with a past history of subcutaneous injection of aesthetic filler material in the lower legs, who presented with post-infectious glomerulonephritis following necrotic leg ulcers at the injection site. Kidney biopsy revealed the presence of translucent, non-birefringent microspherical bodies compatible with polymethylmetacrylate (PMMA) microspheres in some capillary lumens. This had not previously been described. PMMA is a biphasic aesthetical filler composed of polymethylmetacrylate microspheres suspended in a biodegradable bovine collagen carrier. The solid phase (PMMA microspheres) persists in tissues for years. Although PMMA was thought to not disseminate systemically, tissue necrosis may have favored systemic dissemination of the microspheres, although entry in the circulation and microembolization at the time of administration cannot be ruled out.

Conclusions

In conclusion, aesthetic filler implants may cause microembolization into small vessels. Recognition of the characteristic morphology may expedite diagnosis and avoid unnecessary further testing.

Cryoglobulinemic Glomerulonephritis as a Presentation of Atypical Post-Infectious Glomerulonephritis

Post-infectious glomerulonephritis (PIGN) usually occurs within few days to weeks following an infection. Clinical presentation is variable, but in general, it is considered a benign entity with good prognosis. It rarely requires kidney biopsy to confirm the diagnosis. We present a case of a 55-year-old, previously healthy, male who presented for worsening shortness of breath, persistent cough, and right-sided pleuritic chest pain. Initial workup revealed a right exudative effusion with empyema. Hospital course was complicated by acute kidney injury requiring renal replacement therapy with a peak creatinine of 10.2 mg/dL from a baseline of 1.18 mg/dL. On kidney biopsy, findings were compatible with a diagnosis of cryoglobulinemic glomerulonephritis or an atypical form of PIGN. While a wide variety of histopathological findings on renal biopsies have been described to complement the usual diffuse proliferative glomerulonephritis pattern, cryoglobulinemic features with negative cryoglobulin have never been reported. Our case is unique not only by having an atypical histological presentation but also by meeting the criteria of atypical PIGN with persistent hypertension and microscopic hematuria.

Albuminuria and its associated biomedical factors among indigenous adults in Far North Queensland: a 7-year follow up study

BACKGROUND

To document albuminuria prevalence and its associated factors in Aboriginal and Torres Strait Islander (TSI) adults with high renal and metabolic risks from 19 rural and remote north Queensland communities.

METHODS

One thousand nine hundred seventy-one indigenous adults were enrolled in 1998 and 566 completed follow up in 2007 in this population-based study. Measurements included weight, waist circumference (WC), blood pressure (BP), fasting glucose, lipids, gamma-glutamyltransferase (GGT), urinary albumin creatinine ratio (UACR), smoking, alcohol intake and physical activity (PA). Albuminuria was defined as an UACR > =2.5 g/mol in males and > =3.5 g/mol in females. The association between albuminuria and biomedical factors was assessed with generalised linear modelling.

RESULTS

Baseline albuminuria prevalence was 19.7 % (95 % CI: 18.0-21.6 %). Follow up prevalence was 42.4 % (95 % CI: 38.4-46.5 %) among the 566 adults having the 2(nd) UACR measurements. Follow-up albuminuria was associated with fasting glucose of 5.4 mmol/L (OR 2.5, 95 % CI 1.5-4.2), GGT tertiles in a dose-response manner (OR 2.0 for 2(nd) and 3.7 for 3(rd) tertile, p for trend <0.001), and abdominal overweight and obesity (OR 2.1, 95 % CI 1.1-3.9 and 5.4, 95 % CI: 2.2-13.5 respectively). Aboriginal people with diabetes were three times more likely of having albuminuria compared to TSI counterparts, while TSI smokers had twice the likelihood (95 % CI 1.2-3.2). At both baseline and follow up, albuminuria was more prevalent among older participants.

CONCLUSIONS

Indigenous Australians in north Queensland are at high risk of albuminuria. Overweight and obesity, glycaemia, increased GGT, and smoking were associated with albuminuria at baseline and/or follow up.

The Global Epidemiology of Impetigo: A Systematic Review of the Population Prevalence of Impetigo and Pyoderma

Objective

We conducted a comprehensive, systematic review of the global childhood population prevalence of impetigo and the broader condition pyoderma.

Methods

PubMed was systematically searched for impetigo or pyoderma studies published between January 1 1970 and September 30 2014. Two independent reviewers extracted data from each relevant article on the prevalence of impetigo.

Findings

Sixty-six articles relating to 89 studies met our inclusion criteria. Based on population surveillance, 82 studies included data on 145,028 children assessed for pyoderma or impetigo. Median childhood prevalence was 12·3% (IQR 4·2–19·4%). Fifty-eight (65%) studies were from low or low-middle income countries, where median childhood prevalences were 8·4% (IQR 4·2–16·1%) and 14·5% (IQR 8·3–20·9%), respectively. However, the highest burden was seen in underprivileged children from marginalised communities of high-income countries; median prevalence 19·4%, (IQR 3·9–43·3%).

Conclusion

Based on data from studies published since 2000 from low and low-middle income countries, we estimate the global population of children suffering from impetigo at any one time to be in excess of 162 million, predominantly in tropical, resource-poor contexts. Impetigo is an under-recognised disease and in conjunction with scabies, comprises a major childhood dermatological condition with potential lifelong consequences if untreated.

Seropositivity for Antibodies to DRS-G, a Virulence Factor from Streptococcus dysgalactiae subsp. equisimilis, Is an Independent Risk Factor for Poststreptococcus Glomerulonephritis and Chronic Kidney Disease in Mumbai, India

The disease spectrum caused by Streptococcus dysgalactiae subsp. equisimilis resembles that of S. pyogenes (group A streptococcus [GAS]). These two bacterial species are closely related and possess many common virulence characteristics. While some GAS strains express virulence factors called streptococcal inhibitor of complement (SIC) and distantly related to SIC (DRS), some S. dysgalactiae subsp. equisimilis isolates express an orthologue of DRS, which is referred to as DRS-G. We reported previously that seropositivity for either anti-SIC or anti-DRS antibodies (Abs) is associated with poststreptococcal glomerulonephritis (PSGN). However, only seropositivity for anti-SIC Abs is associated with chronic kidney disease (CKD). We now extend the study to test whether seropositivity for anti-DRS-G Abs is also associated with these renal diseases. Stored serum samples collected for our previous study were tested by an enzyme-linked immunosorbent assay (ELISA) for Abs to DRS-G. The samples represented sera from 100 CKD adult patients, 70 adult end-stage renal disease (ESRD) patients, 25 PSGN pediatric patients, and corresponding age-matched control subjects. The proportion of PSGN, CKD, and ESRD patients who showed seroreaction to anti-DRS-G Abs was significantly higher than that of the corresponding age-matched controls, who in general exhibited seropositivity rates commensurate with the isolation rate of drsG-positive S. dysgalactiae subsp. equisimilis in the community during this study period. Since higher rates of seropositivity for anti-DRS-G Abs in the renal disease categories are resultant of previous infections with DRS-G-positive S. dysgalactiae subsp. equisimilis strains, we conclude the seropositivity is an additional risk factor for these renal diseases. In this regard, anti-DRS-G Abs have attributes similar to those of the anti-SIC Abs.

Enigmatic pruritus in a kidney transplant patient

Pruritus is a common problem following a kidney transplant and is usually attributable to new medications related to transplantation. We present an unusual case of pruritus that began several months after kidney transplantation. After changing several immunosuppressive medications, numerous clinical visits and consideration by the patient of stopping immunosuppression, scabies was diagnosed as the cause. Treatment with oral ivermectin and topical permethrin resulted in complete resolution of symptoms within 1 week. Transplant physicians should consider common causes of pruritus unrelated to transplantation; diagnostic skin lesions of scabies may be absent.

Ten-Year Follow-up of Patients with Epidemic Post Infectious Glomerulonephritis

Background

Scarce information on outcomes of epidemic post infectious glomerulonephritis is available. This is a 10-year follow-up of the patients that developed acute glomerulonephritis in an epidemic outbreak caused by group C Streptococcus zooepidemicus in Brazil in 1998, that were also previously evaluated 2 and 5 years after the acute episode.

Methods

In this prospective study 60 cases (out of 134 in 1998) were reevaluated after 10 years, as well as community controls matched by gender and age. They underwent clinical and renal function evaluation, including serum creatinine and cystatin C, estimated glomerular filtration rate (eGFR), albuminuria and hematuria.

Results

Comparisons of clinical and renal function aspects of 60 patients and 48 community controls have not shown significant differences (eGFR <60 ml/min/1.73m² and/or albuminuria >30mg/g creatinine: 13.8% vs. 12.2%, respectively, p = 0.817) except for a higher frequency of hypertension in the cases (45.0% vs. 20.8%, p = 0.009). Comparing the same patients affected in the acute episode, 2, 5 and 10 years later, it was observed an improvement of median eGFR levels at 2 years and a trend toward subsequent stabilization in these levels, associated with decrease in albuminuria and increased hypertension rates in the last survey. At 10 years it was not observed additional reduction of renal function using serum creatinine, eGFR and cystatin C.

Conclusions

During the acute episode of epidemic GN a considerable proportion of patients presented hypertension and reduced renal function; after 2 years and particularly at this 10-year follow-up survey there was no worsening of renal function parameters, except for persistent higher frequency of hypertension. Nevertheless, a longer follow up is necessary to confirm that progressive loss of renal function will not occur.

Post-infectious group A streptococcal autoimmune syndromes and the heart

There is a pressing need to reduce the high global disease burden of rheumatic heart disease (RHD) and its harbinger, acute rheumatic fever (ARF). ARF is a classical example of an autoimmune syndrome and is of particular immunological interest because it follows a known antecedent infection with group A streptococcus (GAS). However, the poorly understood immunopathology of these post-infectious diseases means that, compared to much progress in other immune-mediated diseases, we still lack useful biomarkers, new therapies or an effective vaccine in ARF and RHD. Here, we summarise recent literature on the complex interaction between GAS and the human host that culminates in ARF and the subsequent development of RHD. We contrast ARF with other post-infectious streptococcal immune syndromes - post-streptococcal glomerulonephritis (PSGN) and the still controversial paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS), in order to highlight the potential significance of variations in the host immune response to GAS. We discuss a model for the pathogenesis of ARF and RHD in terms of current immunological concepts and the potential for application of in depth "omics" technologies to these ancient scourges.

Trends in health status and chronic disease risk factors over 10-14 years in a remote Australian community: a matched pair study

OBJECTIVE

To determine trends in health status over a 10-year interval in a high-risk remote Australian Aboriginal community.

METHODS

Two health surveys were performed, one between 1992 and 1997 and the other between 2004 and 2006, on people aged five years or older. Outcomes were compared across age-matched and sex-matched pairs.

RESULTS

There were 1,209 matched pairs. In the second survey, birthweights tended to be higher, and there were significant increases in heights of adolescents and young adults, and high density lipoprotein cholesterol (HDL-C) levels generally. Young adult males were lighter, had lower measurements for waist circumference and blood pressure and less frequently had overt-albuminuria, while elevated blood pressure was less common in older males. However, females≥15 years had higher measurements for waist circumference, waist to hip ratio (WHR), body mass index (BMI) and diastolic blood pressure and a higher proportion of diabetes, notably in those aged older than 45 years. Males aged 15-24 years were less likely to be smokers while women aged less than 45 years were more often current drinkers.

CONCLUSIONS

Results indicative of better nutrition among youth, better health of young adult males, stable or lower levels of albuminuria and improved HDL levels are all encouraging. The waist circumference increase in females might reflect better food access. An increase in diabetes in older subjects probably reflects recent enhanced survival of middle-aged and older people with--and at risk for--diabetes.

Antibodies to group A streptococcal virulence factors, SIC and DRS, increase predilection to GAS pyoderma

BACKGROUND

Streptococcus pyogenes (group A streptococcus; GAS) is an etiological agent for pharyngitis, pyoderma, and invasive infections in humans. Pharyngitis and pyoderma may lead to serious immune sequelae such as rheumatic heart disease and post-streptococcal glomerulonephritis (PSGN). Streptococcal Inhibitor of Complement (SIC) and its orthologue, distantly related to SIC (DRS), are virulence factors expressed by only four of more than 100 M types of GAS. These four types (M1, M57, M12 and M55) are among the M types, which are associated with PSGN. In several populations PSGN has been shown to be a risk factor for chronic kidney disease (CKD) and end-stage renal disease (ESRD). Previous studies showed SIC or DRS antibody-prevalence was associated with PSGN, and seroprevalence of SIC antibodies is significantly high among CKD and ESRD patients in Mumbai.

METHODS

Streptococcal isolates recovered from GAS pyoderma cases were typed. Seropositivity for SIC and DRS antibodies in subjects with pyoderma, PSGN pediatric cases, age matched healthy controls and non-GAS pyoderma cases were determined.

RESULTS

We confirm in this study an association between seroprevalence to SIC and DRS antibodies, and PSGN in Mumbai population despite low point prevalence of M1, M12, M55 and M57. In addition we extended the study to GAS-pyoderma and non-GAS pyoderma cases. To our surprise, we found a positive association between the seroprevalence to SIC and DRS antibodies, and GAS-pyoderma owing to infection with diverse M types. The mechanism of increased predisposition to pyoderma owing to infection by diverse GAS among SIC or DRS antibody-positive population is not clear. Nonetheless, our findings could be explained by a phenomenon akin to antibody-dependent enhancement (ADE).

CONCLUSIONS

This is the first report showing a small number of GAS M types conferring predisposition to pyoderma by diverse types. Implications of this ADE-like phenomenon are discussed in the light of evolutionary advantage to GAS, vaccine design and control of renal diseases.

Reduced nephron endowment in the neonates of Indigenous Australian peoples

Rates of chronic kidney disease (CKD) among Indigenous groups in Australia exceed non-Indigenous rates eight-fold. Using kidney volume as a surrogate for nephron number, we carried out a study to determine if Indigenous neonates have a smaller kidney volume (and thus a reduced nephron number) from birth compared with non-Indigenous neonates. We recruited term and preterm neonates (<32 weeks) at a tertiary care neonatal unit over a 12 months period. Preterm neonates were assessed (renal sonography and renal function measurement) at 32 weeks corrected age (CA) and again at 38 weeks CA when blood pressure was also measured. All term neonates were assessed in the first post-natal week, including renal sonography, renal function and blood pressure measurement. The primary outcome measured was total kidney volume (TKV) and estimated glomerular filtration rate (eGFR) was a secondary outcome. Data was available for 44 preterm (11 Indigenous) and 39 term (13 Indigenous) neonates. TKV of Indigenous neonates was significantly lower at 32 weeks [12.0 (2.0) v. 15.4 (5.1) ml; P=0.03] and 38 weeks CA [18.6 (4.0) v. 22.6 (5.9) ml; P=0.04] respectively. Term Indigenous neonates also had smaller kidney volumes compared with non-Indigenous neonates. Despite a smaller kidney volume (and reduced nephron number), Indigenous neonates did not have a significantly lower eGFR. Indigenous neonates achieve similar eGFRs to Non-Indigenous neonates, presumably through a higher single nephron filtration rate. This places Indigenous neonates at a greater risk of long-term kidney damage later in life.

Parasitic scabies mites and associated bacteria joining forces against host complement defence

Scabies is a ubiquitous and contagious skin disease caused by the parasitic mite Sarcoptes scabiei Epidemiological studies have identified scabies as a causative agent for secondary skin infections caused by Staphylococcus aureus and Streptococcus pyogenes. This is an important notion, as such bacterial infections can lead to serious downstream life-threatening complications. As the complement system is the first line of host defence that confronts invading pathogens, both the mite and bacteria produce a large array of molecules that inhibit the complement cascades. It is hypothesised that scabies mite complement inhibitors may play an important role in providing a favourable micro-environment for the establishment of secondary bacterial infections. This review aims to bring together the current literature on complement inhibition by scabies mites and bacteria associated with scabies and to discuss the proposed molecular link between scabies and bacterial co-infections.

Paediatric nephrology: the last 50 years

In 1965, the specialty of paediatric nephrology was in its infancy. Following the development of a landmark collaborative research study, the International Study of Kidney Disease in Childhood in the mid-1960s, the first specialist societies were formed: the European Society of Pediatric Nephrology in 1967 and the American Society of Pediatric Nephrology in 1969. The extraordinary improvements in care delivered to children with kidney disease over the past 50 years are too broad to cover in any one paper. They traverse the spectrum of diagnosis, classification, therapeutics, social well-being and transition to adult care. We have selected four case scenarios to highlight these changes in key areas of paediatric nephrology: post-streptococcal glomerulonephritis, nephrotic syndrome, haemolytic uraemic syndrome and neonatal dialysis and childhood transplantation.

Kidney disease in Aboriginal Australians: a perspective from the Northern Territory

This article outlines the increasing awareness, service development and research in renal disease in Aboriginal people in Australia's Northern Territory, among whom the rates of renal replacement therapy (RRT) are among the highest in the world. Kidney failure and RRT dominate the intellectual landscape and consume the most professional energy, but the underlying kidney disease has recently swung into view, with increasing awareness of its connection to other chronic diseases and to health profiles and trajectories more broadly. Albuminuria is the marker of the underlying kidney disease and the best treatment target, and glomerulomegaly and focal glomerulosclerosis are the defining histologic features. Risk factors in its multideterminant genesis reflect nutritional and developmental disadvantage and inflammatory/infectious milieu, while the major putative genetic determinants still elude detection. A culture shift of "chronic disease prevention" has been catalyzed in part by the human pain, logistic problems and great costs associated with RRT. Nowadays chronic disease management is the central focus of indigenous primary care, with defined protocols for integrated testing and management of chronic diseases and with government reimbursed service items and free medicines for people in remote areas. Blood pressure, cardiovascular risk and chronic kidney disease (CKD) are all mitigated by good treatment, which centres on renin-angiotensin system blockade and good metabolic control. RRT incidence rates appear to be stabilizing in remote Aboriginal people, and chronic disease deaths rates are falling. However, the profound levels of disadvantage in many remote settings remain appalling, and there is still much to be done, mostly beyond the direct reach of health services.

Standardising and assessing digital images for use in clinical trials: a practical, reproducible method that blinds the assessor to treatment allocation

With the increasing availability of high quality digital cameras that are easily operated by the non-professional photographer, the utility of using digital images to assess endpoints in clinical research of skin lesions has growing acceptance. However, rigorous protocols and description of experiences for digital image collection and assessment are not readily available, particularly for research conducted in remote settings. We describe the development and evaluation of a protocol for digital image collection by the non-professional photographer in a remote setting research trial, together with a novel methodology for assessment of clinical outcomes by an expert panel blinded to treatment allocation.

Atypical presentation of post infectious glomerulonephritis as malignant hypertension and thrombotic microangiopathy

Infection-related glomerulonephritis presents commonly as acute nephritic illness, hypertension, hypocomplementinemia following an episode of pharyngitis or pyoderma. Atypical features like thrombotic microangiopathy (TMA), produced by neuraminidase antigen targeting endothelium have been described rarely. We report a case of TMA secondary to malignant hypertension, coexisting with post infectious glomerulonephritis.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Decreasing rates of natural deaths in a remote Australian Aboriginal community, 1996-2010

OBJECTIVE

To examine the trends of all-cause natural mortality for people aged 15 years and over in a remote Australian Aboriginal community between 1996 and 2010.

METHODS

The annual population in the community by gender and age group was obtained from the Australian Bureau of Statistics (ABS). All known deaths and all records of start of renal replacement therapy (RRT) for renal failure were recorded between 1996 and 2010. Five-year aggregated death rates were calculated and the changes in natural mortality over the interval were evaluated. Mortality was compared with those of the Northern Territory (NT) Indigenous and non-Indigenous people as a whole from 1998 to 2006.

RESULTS

Rates of natural deaths were lower in the third interval 2006-2010 relative to the first interval 1996-2000, with higher, but more rapidly falling rates for females than males. Reductions were prominent for both sexes in the 65 and over age groups, but death rates in females of earlier middle age also trended lower. The trends applied whether or not the starting of RRT was considered as a natural death. There was a similar trend in rates of natural death in the aggregate Indigenous population of NT.

CONCLUSIONS

The downward trends probably reflect improvements in risk factor status since the 1960s, all-of-life health interventions, as well as better chronic disease management in the last two decades. The higher death rates in females than males in this community remain unexplained, but the rapid rate of decline of female death rates predicts that this gap will soon be minimised.

New trends of an old disease: the acute post infectious glomerulonephritis at the beginning of the new millenium

The association between acute renal disease and infection has been known since the mid '800s: acute post-infectious glomerulonephritis (PIGN) is a reactive immunological process against the kidney secondary to an infection, classically caused by a Streptococcus. The typical clinical presentation of PIGN is an acute nephritic syndrome with macro- or microscopic hematuria, proteinuria, hypertension, edema and renal function impairment of variable degree. The histology is characterized by an intracapillary glomerular proliferation, but may rarely be associated with an extracapillary proliferation. The classical childhood form is still present nowadays, even with severe cases, in developing countries, while in the last decades it almost disappeared in industrialized countries, where post-infectious GN are often found in elderly patients with multiple comorbidities. These clinical variants are usually related to other infective agents, like Staphylococcus aureus, both methicillin resistant (MRSA) and susceptible, and may be characterized by an IgA-dominant deposition. Kidney biopsy is rarely needed, especially in the child, while in the adult or old patient a biopsy is warranted if there is an atypical presentation or evolution, like rapidly progressive renal failure, absent or delayed function recovery, persisting low C3, nephrotic range proteinuria and persisting high proteinuria. Current therapy strategies rely on culture-guided systemic antibiotics, especially in the old patient, in which MRSA are relatively frequent, support therapy and only in very selected cases on steroids. These latter cases include the rare PIGN with crescents and those with a severe interstitial inflammation.

Prospective population-based study on the burden of disease from post-streptococcal glomerulonephritis of hospitalised children in New Zealand: epidemiology, clinical features and complications

AIM

A nationwide 24-month study was conducted (2007-2009), via the New Zealand Paediatric Surveillance Unit to define epidemiology and clinical features of acute poststreptococcal glomerulonephritis (APSGN) in children hospitalised with the illness.

METHODS

Paediatricians (n = 215) were requested to report new hospitalised cases fulfilling a case definition of definite (haematuria with low C3 and high streptococcal titres or biopsy proven APSGN) or probable (haematuria with low C3 or high streptococcal titres).

RESULTS

A total of 176 cases were identified (definite: n = 138, probable: n = 38) with 63% residing in the Auckland metropolitan region. Sixty-seven percent were in the most deprived quintile. Annual incidence (0-14 years) was 9.7/100,000 (Pacific 45.5, Maori 15.7, European/other 2.6 and Asian 2.1/100,000). Annual incidence was highest in the South Auckland Metropolitan region (31/100,000), Central Auckland 14.9, West/North Auckland metropolitan region 5.9 and for the remainder of New Zealand 5.5/100,000. Age-specific incidence was highest in age 5-9 years (15.1/100,000). Reduced serum complement C3, gross haematuria, hypertension, impairment of renal function and heavy proteinuria were present in 93%, 87%, 72%, 67% and 44% of patients, respectively. Severe hypertension was closely associated with either symptoms of an acute encephalopathy or congestive heart failure.

CONCLUSIONS

New Zealand children carry a significant disease burden of hospitalised APSGN with socio-economically deprived; Pacific and Maori children are being over-represented. Significant short-term complications were observed in hospitalised children with APSGN. Persistently very low rates in European/other suggest a preventable disease.

The elimination of scabies: a task for our generation

Scabies prevalence remains unacceptably high in many regions throughout the world. Infestation with scabies significantly impacts quality of life and is linked to pyoderma and consequently to severe long-term sequelae such as post-streptococcal glomerulonephritis. In the past, control programs using topical treatments have met with poor compliance; however, the highly effective oral agent ivermectin may offer a new paradigm in scabies management. Problems still exist with insensitive diagnostic tests, questions concerning mite reservoirs, and restrictions on who can receive ivermectin. Despite these difficulties, the elimination of scabies in communities worst affected may soon be possible.

Seroprevalence of Streptococcal Inhibitor of Complement (SIC) suggests association of streptococcal infection with chronic kidney disease

BACKGROUND

Group A streptococcus (GAS) is an etiological agent for the immune mediated sequela post streptococcal glomerulonephritis (PSGN). In some populations PSGN is recognized as a risk factor for chronic kidney disease (CKD) and end-stage renal disease (ESRD). It was found that a significantly greater proportion of subjects with past history of PSGN than without the history exhibited seroreactions to streptococcal antigens called streptococcal inhibitor of complement (SIC) and to distantly related SIC (DRS). These antigens are expressed by major PSGN-associated GAS types. We therefore predicted that in populations such as India, which is endemic for streptococcal diseases and which has high prevalence of CKD and ESRD, greater proportions of CKD and ESRD patients exhibit seroreaction to SIC and DRS than healthy controls.

METHODS

To test this we conducted a SIC and DRS seroprevalence study in subjects from Mumbai area. We recruited 100 CKD, 70 ESRD and 70 healthy individuals.

RESULTS

Nineteen and 35.7% of CKD and ESRD subjects respectively were SIC antibody-positive, whereas only 7% of healthy cohort was seropositive to SIC. Furthermore, significantly greater proportion of the ESRD patients than the CKD patients is seropositive to SIC (p=0.02; odds ratio 2.37). No association was found between the renal diseases and DRS-antibody-positivity.

CONCLUSIONS

Past infection with SIC-positive GAS is a risk factor for CKD and ESRD in Mumbai population. Furthermore, SIC seropositivity is predictive of poor prognosis of CKD patients.