Utility of quantitative sensory testing and screening tools in identifying HIV-associated peripheral neuropathy in Western Kenya: pilot testing

Robiginitalea marina sp. nov., isolated from coastal sediment

A Gram-stain-negative, orange, aerobic, non-motile, rod-shaped marine bacterium, designated as 2V75^T, was isolated from the coastal sediment of Xiaoshi Island, Weihai, China. The strain 2V75^T grew at 20-45 °C (optimum, 37 °C), from pH 7.0 to 9.0 (optimum, pH 7.0) and in the presence of 0.5-5% (w/v) NaCl (optimum, 3%). Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain 2V75^T was affiliated to the genus Robiginitalea and had the highest sequence similarity with R. biformata KCTC 12146^T (93.7%). The ANI values between strain 2V75^T and R. biformata KCTC 12146^T were 72.6%, respectively. The DNA G + C content was 54.8 mol%. MK-6 was the only respiratory quinone. Based on the phenotypic, phylogenetic and chemotaxonomic data, strain 2V75^T should be classified as a novel species in the genus Robiginitalea, for which the name Robiginitalea marina is proposed. The type strain is 2V75^T (= KCTC 92035^T = MCCC 1H00484^T).

Comparative genomic analysis of the genus Marinomonas and taxonomic study of Marinomonas algarum sp. nov., isolated from red algae Gelidium amansii

Members of the genus Marinomonas are known for their environmental adaptation and metabolically versatility, with abundant proteins associated with antifreeze, osmotic pressure resistance, carbohydrase and multiple secondary metabolites. Comparative genomic analysis focusing on secondary metabolites and orthologue proteins was conducted with 30 reference genome sequences in the genus Marinomonas. In this study, a Gram-stain-negative, rod-shaped, non-flagellated and strictly aerobic bacterium, designated as strain E8^T, was isolated from the red algae (Gelidium amansii) in the coastal of Weihai, China. Optimal growth of the strain E8^T was observed at temperatures 25-30 °C, pH 6.5-8.0 and 1-3% (w/v) NaCl. The DNA G + C content was 42.8 mol%. The predominant isoprenoid quinone was Q-8 and the major fatty acids were C_16:0, summed feature 3 and summed feature 8. The major polar lipids were phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). Based on data obtained from this polyphasic taxonomic study, strain E8^T should be considered as a novel species of the genus Marinomonas, for which the name Marinomonas algarum is proposed. The type strain is E8^T (= KCTC 92201^T = MCCC 1K07070^T).

Molecular characteristics of Staphylococcus aureus associated prosthetic joint infections after hip fractures treated with hemiarthroplasty: a retrospective genome-wide association study

A retrospective study of Staphylococcus aureus isolates from orthopaedic patients treated between 2000 and 2017 at Akershus University Hospital, Norway was performed using a genome-wide association approach. The aim was to characterize and investigate molecular characteristics unique to S. aureus isolates from HHA associated prosthetic joint infections and potentially explain the HHA patients’ elevated 1-year mortality compared to a non-HHA group. The comparison group consisted of patients with non-HHA lower-extremity implant-related S. aureus infections. S. aureus isolates from diagnostic patient samples were whole-genome sequenced. Univariate and multivariate analyses were performed to detect group-associated genetic signatures. A total of 62 HHA patients and 73 non-HHA patients were included. Median age (81 years vs. 74 years; p < 0.001) and 1-year mortality (44% vs. 15%, p < 0.001) were higher in the HHA group. A total of 20 clonal clusters (CCs) were identified; 75% of the isolates consisted of CC45, CC30, CC5, CC15, and CC1. Analyses of core and accessory genome content, including virulence, resistance genes, and k-mer analysis revealed few group-associated variants, none of which could explain the elevated 1-year mortality in HHA patients. Our findings support the premise that all S. aureus can cause invasive infections given the opportunity.

Is folate deficiency a common cause of distal symmetric polyneuropathy in Zambian clinics?

OBJECTIVES

To evaluate the odds of vitamin B12 and folate deficiencies among Zambian clinic attendees with distal symmetric polyneuropathy (DSP) and age, sex, and HIV matched controls.

METHODS

Cases were adults from clinics in urban/peri-urban Zambia. Controls were enrolled among persons not seeking personal medical care, such as a caregiver or person collecting antiretrovirals without a medical complaint. Participants underwent structured interviews, physician examination, and assessments of complete blood count, renal and liver profiles, serum vitamin B12 and folate, erythrocyte folate, plasma total homocysteine and methylmalonic acid. HIV testing and CD4 counts were performed when appropriate.

RESULTS

Among 107 consenting matched case-control pairs, 65% were female, 52% HIV positive, with mean age of 47.6 (SD 13.5) years. Among HIV positive participants, mean CD4 count was 484 (SD 221) and 482 (SD 236) for cases and controls, respectively (p = .93). DSP symptoms and severity did not differ by HIV status (p's > 0.05). Height, history of tuberculosis treatment, alcohol use, education, asset index, dietary diversity, and nutritional supplement use did not differ between cases and controls (p's > 0.05). DSP cases had at least 3:1 odds of having low serum folate (p = .0001), severely low erythrocyte folate (p = .014), and elevated total homocysteine (p = .001) levels compared to controls. Markers of vitamin B12 deficiency were not associated with case status (p's > 0.05).

CONCLUSION

Markers of folate deficiency are highly associated with DSP among Zambian clinic attendees. Future studies should consider a broader range of comorbid nutritional deficiencies, and strategies for interventions.

Factors associated with distal symmetric polyneuropathies in adult Zambians: A cross-sectional, observational study of the role of HIV, non-antiretroviral medication exposures, and nutrition

BACKGROUND

Non-antiretroviral (ART) drug exposures and poor nutrition may be important modifiable risk factors for distal symmetric polyneuropathies (DSP) in sub-Saharan Africa.

METHODS

We conducted a cross-sectional study of DSP prevalence and factors associated with DSP among clinic attendees in urban and rural Zambia. All participants underwent neurologist-performed examination. Laboratory investigations seeking comorbid risk factors for DSP were performed for DSP cases.

RESULTS

We identified 31/137 (22.6%) HIV+ and 21/177 (11.9%) HIV- DSP cases. DSP prevalence did not differ by urbanicity, although rural participants were significantly more likely to have one asymptomatic DSP sign. Low dietary diversity, history of syphilis, history of tuberculosis, and prior metronidazole and ciprofloxacin use were associated with DSP amongst HIV+ cases, while age and education were associated with DSP in HIV- participants (all p-values < 0·05). In a multivariate logistic regression model, HIV (p = 0·0001) and age (p < 0·0001), and ciprofloxacin exposure (p = 0·01) remained independently associated with DSP. While diabetes was rare, supoptimal micronutrients levels were common among DSP cases regardless of HIV status.

CONCLUSIONS

While HIV infection is strongly associated with DSP in Zambia, history of non-ART drug exposures and low dietary diversity are also important determinants of DSP in HIV+ individuals. Treatable micronutrient deficiencies were common.

Peripheral neuropathy in HIV-infected and uninfected patients in Rakai, Uganda

OBJECTIVE

To determine the prevalence, risk factors, and functional impairment associated with peripheral neuropathy in a prospective cohort of adults in rural Uganda.

METHODS

Eight hundred participants (400 HIV- and 400 antiretroviral-naive HIV+) in the Rakai Community Cohort Study underwent detailed neurologic evaluations including assessment of neuropathy symptoms, functional measures (Patient Assessment of Own Functioning Inventory and Karnofsky Performance Status scores), and neurologic evaluation by a trained medical officer. Neuropathy was defined as ≥1 subjective symptom and ≥1 sign of neuropathy on examination. Neuropathy risk factors were assessed using log binomial regression.

RESULTS

Fifty-three percent of participants were men, with a mean (SD) age of 35 (8) years. Neuropathy was present in 13% of the cohort and was more common in HIV+ vs HIV- participants (19% vs 7%, p < 0.001). Older age (relative risk [RR] 1.04, 95% confidence interval [CI] 1.02-1.06), female sex (RR 1.49, 95% CI 1.04-2.15), HIV infection (RR 2.82, 95% CI 1.86-4.28), tobacco use (RR 1.59, 95% CI 1.02-2.48), and prior neurotoxic medication use (RR 2.08, 95% CI 1.07-4.05) were significant predictors of neuropathy in the overall cohort. Only older age was associated with neuropathy risk in the HIV+ (RR 1.03, 95% CI 1.01-1.05) and HIV- (RR 1.06, 95% CI 1.02-1.10) cohorts. Neuropathy was associated with impaired functional status on multiple measures across all participant groups.

CONCLUSIONS

Peripheral neuropathy is relatively common and associated with impaired functional status among adults in rural Uganda. Older age, female sex, and HIV infection significantly increase the risk of neuropathy. Neuropathy may be an underrecognized but important condition in rural Uganda and warrants further study.

Genetics of HIV-associated sensory neuropathy and related pain in Africans

Despite the use of safer antiretroviral medications, the rate of HIV-associated sensory neuropathy (HIV-SN), the most common neurological complication of HIV, remains high. This condition is often painful and has a negative effect on quality of life. Up to 90% of those with HIV-SN experience pain for which there is no effective analgesic treatment. Genetic factors are implicated, but there is a lack of a comprehensive body of research for African populations. This knowledge gap is even more pertinent as Africans are most affected by HIV. However, recent studies performed in Southern African populations have identified genes displaying potential as genetic markers for HIV-SN and HIV-SN-associated pain in Africans. Here, we review the published studies to describe current knowledge of genetic risk factors for this disease in Africa.

The Protease Inhibitor Monotherapy Versus Ongoing Triple Therapy (PIVOT) trial: a randomised controlled trial of a protease inhibitor monotherapy strategy for long-term management of human immunodeficiency virus infection

BACKGROUND

Standard-of-care antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection uses a combination of drugs, until now considered essential to minimise treatment failure and development of drug resistance. Protease inhibitors (PIs) are potent with a high genetic barrier to resistance and have the potential for use as monotherapy after viral load (VL) suppression achieved on combination therapy. However, longer-term resistance and toxicity risks are uncertain.

OBJECTIVE

To compare the effectiveness, toxicity profile and cost-effectiveness of PI monotherapy with those of standard-of-care triple therapy in a pragmatic long-term clinical trial.

DESIGN

Open-label, parallel-group, randomised controlled trial.

SETTING

Forty-three HIV clinical centres in the UK NHS.

PARTICIPANTS

HIV-positive adults taking standard combination ART with a suppressed VL for ≥ 6 months.

INTERVENTIONS

Patients were randomised to maintain ongoing triple therapy (OT) or switch to a strategy of physician-selected ritonavir-boosted PI monotherapy (PI-mono), with prompt return to combination therapy in the event of VL rebound.

MAIN OUTCOME MEASURES

The primary outcome was reduction of future drug options, defined as new intermediate-/high-level resistance to one or more drugs to which the patient's virus was considered to be sensitive at trial entry (non-inferiority comparison, 10% margin). Secondary outcomes included confirmed virological rebound, serious drug- or disease-related complications, total grade 3 or 4 adverse events (AEs), neurocognitive function change, cluster of differentiation 4 (CD4) cell count change, change in health-related quality of life, cardiovascular risk change, health-care costs and health economic analysis.

RESULTS

In total, 587 participants were randomised (77% male, 68% white) to OT (n = 291) or PI-mono (n = 296) and followed for a median of 44 months, of whom 2.7% withdrew/were lost to follow-up. One or more episodes of confirmed VL rebound were observed in eight patients (Kaplan-Meier estimate 3.2%) in the OT group and 95 patients (35.0%) in the PI-mono group [absolute risk difference 31.8%, 95% confidence interval (CI) 24.6% to 39.0%; p < 0.001]. PI-mono patients who changed to ART after VL rebound all resuppressed (median 3.5 weeks). The proportions with loss of a future drug option at 3 years were 0.7% in the OT group and 2.1% in the PI-mono group (difference 1.4%, (95% CI -0.4% to 3.4%); non-inferiority demonstrated). There were no significant differences in serious disease complications between groups or in the frequency of grade 3 or 4 clinical AEs (16.8% OT group vs. 22% PI-mono group; absolute risk difference 5.1%, 95% CI -1.3% to 11.5%; p = 0.12). Overall, the PI-mono strategy was shown to be cost-effective compared with OT under most scenarios explored. PI-mono was cost saving because of the large savings in ART drug costs while being no less effective in terms of quality-adjusted life-years in the within-trial analysis and only marginally less effective when extrapolated to lifetime outcomes.

CONCLUSIONS

PI monotherapy, with prompt reintroduction of combination therapy for VL rebound, was non-inferior to combination therapy in preserving future treatment options and is an acceptable and cost-effective alternative for long-term management of HIV infection.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN04857074.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 21. See the NIHR Journals Library website for further project information.

Prevalent neuropathy in a cohort of HIV-infected Kenyan sex workers using antiretroviral drugs

INTRODUCTION

Several risk factors including stavudine and age have been strongly associated with polyneuropathy. However, conflicting data exist on height as an independent risk factor in polyneuropathy. The objective of this study is to exclude height as an independent polyneuropathy risk factor in a cohort of human immunodeficiency virus (HIV)-infected Kenyan sex workers.

METHODS

This was an analysis of prospectively collected data of treatment-naive subjects initiating either stavudine or tenofovir diphosphate fumarate or zidovudine-based antiretroviral therapy (ART) regimens from January 2008 to August 2012. Polyneuropathy was characterised as burning sensation, numbness, or dysesthesia. The study used arithmetic means of weight (kg) and height (cm) measured in duplicates using calibrated scales.

RESULTS

After exclusion of duplicate data sets and un-confirmed cases of polyneuropathy, the study identified 212 patients without polyneuropathy, 14 pre-ART and 94 post-ART related polyneuropathy cases. Polyneuropathy cases were older but did not differ in demographic, clinical and laboratory parameters at baseline. There was a significant difference in first-line ART regimens with more patients on tenofovir disoproxil fumarate in the post-ART group (p=0.017).

CONCLUSION

Polyneuropathy is a common disorder among HIV-infected Kenyan sex workers. These data cannot support the postulated increased risk by height after matching for gender and ART duration. Though stavudine is associated with polyneuropathy, in this study many patients previously not exposed to stavudine developed polyneuropathy. This suggests the involvement of unknown risk factors such as genetic and metabolite differences in the development of polyneuropathy.

Peripheral neuropathy in HIV patients in sub-Saharan Africa failing first-line therapy and the response to second-line ART in the EARNEST trial

Sensory peripheral neuropathy (PN) remains a common complication in HIV-positive patients despite effective combination anti-retroviral therapy (ART). Data on PN on second-line ART is scarce. We assessed PN using a standard tool in patients failing first-line ART and for 96 weeks following a switch to PI-based second-line ART in a large Randomised Clinical Trial in Sub-Saharan Africa. Factors associated with PN were investigated using logistic regression. Symptomatic PN (SPN) prevalence was 22% at entry (N = 1,251) and was associated (p < 0.05) with older age (OR = 1.04 per year), female gender (OR = 1.64), Tuberculosis (TB; OR = 1.86), smoking (OR = 1.60), higher plasma creatinine (OR = 1.09 per 0.1 mg/dl increase), CD4 count (OR = 0.83 per doubling) and not consuming alcohol (OR = 0.55). SPN prevalence decreased to 17% by week 96 (p = 0.0002) following similar trends in all study groups (p = 0.30). Asymptomatic PN (APN) increased over the same period from 21 to 29% (p = 0.0002). Signs suggestive of PN (regardless of symptoms) returned to baseline levels by week 96. At weeks 48 and 96, after adjusting for time-updated associations above and baseline CD4 count and viral load, SPN was strongly associated with TB (p < 0.0001). In summary, SPN prevalence was significantly reduced with PI-based second-line therapy across all treatment groups, but we did not find any advantage to the NRTI-free regimens. The increase of APN and stability of PN-signs regardless of symptoms suggest an underlying trend of neuropathy progression that may be masked by reduction of symptoms accompanying general health improvement induced by second-line ART. SPN was strongly associated with isoniazid given for TB treatment.

Quality of life and self-reported lower extremity function in adults with HIV-related distal sensory polyneuropathy

BACKGROUND

Distal sensory polyneuropathy (DSP) is a common complication of HIV disease. Its effects on quality of life (QOL) and function have not been well described.

OBJECTIVE

The study objectives were: (1) to compare QOL and lower extremity function in people with HIV-related DSP and people with HIV disease who do not have DSP, (2) to determine the extent to which function predicts QOL, (3) to evaluate the agreement of 2 function scales, and (4) to describe the use of pain management resources.

DESIGN

This was a cross-sectional survey study with predictive modeling and measurement tool concordant validation.

METHODS

A demographic questionnaire, the Medical Outcomes Study HIV Health Survey, the Lower Extremity Functional Scale (LEFS), the Lower Limb Functional Index (LLFI), and a review of medical records were used. General linear modeling was used to assess group differences in QOL and the relationship between function and QOL. Bland-Altman procedures were used to assess the agreement of the LEFS and the LLFI.

RESULTS

Usable data for analyses were available for 82 of the 94 participants enrolled. The 67% of participants who reported DSP symptoms tended to be older, had HIV disease longer, and were more likely to receive disability benefits. Participants without DSP had better LLFI, LEFS, and physical health summary scores. In multivariate models, lower limb function predicted physical and mental health summary scores. The LLFI identified participants with a lower level of function more often than the LEFS. Participants with DSP were more likely to use medical treatment, physical therapy, and complementary or alternative treatments.

LIMITATIONS

A sample of convenience was used; the sample size resulted in a low power for the mental health summary score of the Medical Outcomes Study HIV Health Survey.

CONCLUSIONS

Quality of life and function were more impaired in participants with HIV disease and DSP. The LLFI was more likely to capture limitations in function than the LEFS. Participants with DSP reported more frequent use of pain management resources.

Screening for HIV-associated peripheral neuropathy in resource-limited settings

INTRODUCTION

Peripheral neuropathy is the most common neurological complication of human immunodeficiency virus (HIV) infection but is widely under-diagnosed in resource-limited settings. We investigated the utility of screening tools administered by nonphysician healthcare workers (HCW) and quantitative sensory testing (QST) administered by trained individuals for identification of moderate/severe neuropathy.

METHODS

We enrolled 240 HIV-infected outpatients using 2-stage cluster randomized sampling. HCWs administered the several screening tools. Trained study staff performed QST. Tools were validated against a clinical diagnosis of neuropathy.

RESULTS

Participants were 65% women, mean age 36.4 years, median CD4 324 cells/μL. A total of 65% were taking antiretrovirals, and 18% had moderate/severe neuropathy. The screening tests were 76% sensitive in diagnosing moderate/severe neuropathy with negative predictive values of 84-92%. QST was less sensitive but more specific.

CONCLUSIONS

Screening tests administered by HCW have excellent negative predictive values and are promising tools for scale-up in resource-limited settings. QST shows promise for research use.

Frequency and risk factors for distal sensory polyneuropathy in HIV infection in a developing country

Distal sensory polyneuropathy is a source of morbidity in HIV infection. This study aims to determine the frequency and effect of demographic and clinical variables on distal sensory polyneuropathy, among HIV-positive participants in south-east Nigeria. The study involved highly active antiretroviral therapy (HAART)-naive, patients on HAART and HIV-negative matched controls conducted at the University of Nigeria Teaching Hospital, Enugu south-east Nigeria. Distal sensory polyneuropathy was diagnosed with clinical evaluation and the use of Bio Thesiometer, 10 g monofilament and ankle reflex. There were 100 participants in each of the groups, comprising 109 (36.3%) men and 191 (63.7%) women, with median age of 35 years. About 42.5% (85/200) of the HIV-positive participants (37 drug naive and 48 on HAART) had distal sensory polyneuropathy. None in the control group had distal sensory polyneuropathy. Age ( p = 0.02), height ( p = 0.002), low haemoglobin ( p = 0.03) and mean duration on HAART ( p = 0.006) were significantly associated with distal sensory polyneuropathy, while gender ( p = 0.497), body mass index ( p = 0.657) and CD4 count ( p = 0.482) did not affect distal sensory polyneuropathy. Low haemoglobin, height, and duration on HAART were independent risk factors for distal sensory polyneuropathy. Addressing correctable causes of anaemia, and alternatives to neurotoxic HAART may minimize the risk of distal sensory polyneuropathy.

HIV-associated sensory neuropathy in HIV-1 infected patients at the Douala General Hospital in Cameroon: a cross-sectional study

Background

Peripheral neuropathy (PN) which is the most common neurological complication of HIV infection is under recognised and undertreated especially in resource limited settings. This ailment which has a negative impact on the quality of life of HIV/AIDS patients exists in different clinical patterns of which HIV-associated Sensory neuropathy (HIV-SN) is the most common affecting up to two thirds of patients with advanced disease in some settings. In Cameroon where HIV is a major public health problem, the burden of HIV-SN has not yet been well defined.

Methods

Using the Brief Peripheral Neuropathy Screening (BPNS) tool validated by the AIDS Clinical Trial Group (ACTG) we carried out a cross sectional study to determine the prevalence of HIV-SN and its associated factors among HIV-1 patients at the Douala General Hospital between 1^st July and 31^st October 2011. HIV-SN was defined as the presence of neuropathic symptoms and at least an abnormal perception of vibrations of a 128Hz tuning fork on the great toe or abnormal ankle reflexes or both and expressed as a percentage of the study population.

Results

Out of 295 patients studied, 21% had HIV-SN. In HIV-SN patients the median duration of HIV infection was 79.8 months (IQR 46 – 107.5) and their median CD4 count 153cells/μL (IQR 80 – 280). Patient recall and clinical chart review showed that, 83.9% had neuropathic symptoms prior to HAART initiation and 16.1% after HAART initiation. Low CD4 count, history of alcohol intake and history of anti-tuberculosis treatment were strongly associated with HIV-SN (AOR 2.5, 2.8 and 2.9 respectively).

Conclusions

HIV-SN is common among patients with advanced HIV infection in Cameroon. This simple diagnostic tool (BPNS) should therefore be routinely used to detect those with HIV-SN or at risk so as to minimise the negative impact it has on their quality of life.

Neuropsychiatric and socioeconomic status impact antiretroviral adherence and mortality in rural Zambia

We conducted a prospective cohort study of 496 adults starting antiretroviral treatment (ART) to determine the impact of neuropsychiatric symptoms and socioeconomic status on adherence and mortality. Almost 60% had good adherence based upon pharmacy records. Poor adherence was associated with being divorced, poorer, food insecure, and less educated. Longer travel time to clinic, concealing one's human immunodeficiency virus (HIV) status, and experiencing side effects predicted poor adherence. Over a third of the patients had cognitive impairment and poorer cognitive function was also associated with poor adherence. During follow-up (mean 275 days), 20% died-usually within 90 days of starting ART. Neuropsychiatric symptoms, advanced HIV, peripheral neuropathy symptoms, food insecurity, and poverty were associated with death. Neuropsychiatric symptoms, advanced HIV, and poverty remained significant independent predictors of death in a multivariate model adjusting for other significant factors. Social, economic, cognitive, and psychiatric problems impact adherence and survival for people receiving ART in rural Zambia.

Training needs and evaluation of a neuro-HIV training module for non-physician healthcare workers in western Kenya

BACKGROUND

Recent efforts to improve neurological care in resource-limited settings have focused on providing training to non-physician healthcare workers.

METHODS

A one-day neuro-HIV training module emphasizing HIV-associated dementia (HAD) and peripheral neuropathy was provided to 71 health care workers in western Kenya. Pre- and post-tests were administered to 55 participants.

RESULTS

Mean age of participants was 29 years, 53% were clinical officers and 40% were nurses. Self-reported comfort was significantly higher for treating medical versus neurologic conditions (p<0.001). After training, participants identified more neuropathy etiologies (pre=5.6/9 possible correct etiologies; post=8.0/9; p<0.001). Only 4% of participants at baseline and 6% (p=0.31) post-training could correctly identify HAD diagnostic criteria, though there were fewer mis-identified criteria such as abnormal level of consciousness (pre=82%; post=43%; p<0.001) and hallucinations (pre=57%; post=15%; p<0.001).

CONCLUSIONS

Healthcare workers were more comfortable treating medical than neurological conditions. This training significantly improved knowledge about etiologies of neuropathy and decreased some misconceptions about HAD.