Bone marrow stromal cells dictate lanosterol biosynthesis and ferroptosis of multiple myeloma

Ferroptosis has been demonstrated a promising way to counteract chemoresistance of multiple myeloma (MM), however, roles and mechanism of bone marrow stromal cells (BMSCs) in regulating ferroptosis of MM cells remain elusive. Here, we uncovered that MM cells were more susceptible to ferroptotic induction under the interaction of BMSCs using in vitro and in vivo models. Mechanistically, BMSCs elevated the iron level in MM cells, thereby activating the steroid biosynthesis pathway, especially the production of lanosterol, a major source of reactive oxygen species (ROS) in MM cells. We discovered that direct coupling of CD40 ligand and CD40 receptor constituted the key signaling pathway governing lanosterol biosynthesis, and disruption of CD40/CD40L interaction using an anti-CD40 neutralizing antibody or conditional depletion of Cd40l in BMSCs successfully eliminated the iron level and lanosterol production of MM cells localized in the Vk*MYC Vk12653 or NSG mouse models. Our study deciphers the mechanism of BMSCs dictating ferroptosis of MM cells and highlights the therapeutic potential of non-apoptosis strategies for managing refractory or relapsed MM patients.

Outcomes of asymptomatic histologic pyelonephritis of kidney transplant

BACKGROUND

Urinary Tract Infections are the most common post-transplant infection and can have varied presentations. This study aimed to describe the outcomes of kidney transplant recipients with asymptomatic histologic pyelonephritis on allograft biopsy. Histologic Pyelonephritis was defined as neutrophil cast or neutrophilic tubulitis, interstitial infiltrates with predominant neutrophils, and no evidence of rejection or glomerulonephritis on biopsy.

METHODS

The study included 123 kidney transplant recipients, of whom 95 underwent protocol biopsies, and 28 had biopsies for elevated creatinine within the first 2 years of a kidney transplant.

RESULTS

The mean age of the cohort was 55.3 years, with 52% females and 78% deceased donor transplants. The risk factors for asymptomatic histologic pyelonephritis were recipient female sex (OR 1.89, 1.3-2.7, diabetes mellitus (OR 2.479, 1.687-3.645), and deceased donation (OR 1.69, 1.098-2.63). The incidence of asymptomatic pyelonephritis on protocol biopsy was 1.7%, with 52% having positive urine cultures and Escherichia coli being the most common bacteria. Subjects with asymptomatic pyelonephritis had inferior graft survival compared to the matched cohort HR 1.88 (1.06-3.35), p = .0281. In addition, of these 123 subjects, 68 (55%) subsequently developed pyelonephritis, and 34 subjects had pyelonephritis within 6 months after this episode. Subjects with recurrent infections exhibited lower survival HR 2.86 (1.36-6.02) and a trend toward higher rejection risk.

CONCLUSION

Asymptomatic histologic pyelonephritis can occur in kidney transplant recipients and is associated with inferior graft survival.

Tissue-resident alveolar macrophages reduce O3-induced inflammation via MerTK mediated efferocytosis

Lung inflammation, caused by acute exposure to ozone (O3) - one of the six criteria air pollutants - is a significant source of morbidity in susceptible individuals. Alveolar macrophages (AMØs) are the most abundant immune cells in the normal lung and their number increases following O3 exposure. However, the role of AMØs in promoting or limiting O3-induced lung inflammation has not been clearly defined. Here, we used a mouse model of acute O3 exposure, lineage tracing, genetic knockouts, and data from O3-exposed human volunteers to define the role and ontogeny of AMØs during acute O3 exposure. Lineage tracing experiments showed that 12, 24, and 72 h after exposure to O3 (2 ppm) for 3h all AMØs were tissue-resident origin. Similarly, in humans exposed to FA and O3 (200 ppb) for 135 minutes, we did not observe ~21h post-exposure an increase in monocyte-derived AMØs by flow cytometry. Highlighting a role for tissue-resident AMØs, we demonstrate that depletion of tissue-resident AMØs with clodronate-loaded liposomes led to persistence of neutrophils in the alveolar space after O3 exposure, suggesting that impaired neutrophil clearance (i.e., efferocytosis) leads to prolonged lung inflammation. Moreover, depletion of tissue-resident AMØ demonstrated reduced clearance of intratracheally instilled apoptotic Jurkat cells, consistent with reduced efferocytosis. Genetic ablation of MerTK - a key receptor involved in efferocytosis - also resulted in impaired clearance of apoptotic neutrophils followed O3 exposure. Overall, these findings underscore the pivotal role of tissue-resident AMØs in resolving O3-induced inflammation via MerTK-mediated efferocytosis.

A 64-Year-Old Man with Joint Pain

A 64-Year-Old Man with Joint PainA 64-year-old man presented for evaluation of acute oligoarticular joint pain. How do you approach the evaluation, and what is the diagnosis?

Characteristics and graft outcomes of kidney transplant candidates with enteric risk factors and elevated plasma oxalate levels

INTRODUCTION

This study describes patient characteristics and examines graft function of kidney transplant recipients (without primary hyperoxaluria) with elevated plasma oxalate (POx) and enteric risk factors prior to transplant at our institution.

METHODS

Kidney transplant recipients between 2012 to 2020 with elevated POx at the time of kidney transplant evaluation were included. A matched control cohort was gathered using patient/donor age, living/deceased donor type, panel reactive antibody (PRA), kidney donor profile index (KDPI), and human leukocyte antigen (HLA) mismatch as matching variables. Graft function at 1 year and at last follow-up was reported.

RESULTS

A total of 106 patients with elevated POx were identified. A third of the patients had Roux-en-Y gastric bypass, a third had other enteric risks, and a third did not have an identifiable enteric risk. Median eGFR (estimated glomerular filtration rate) at 1-year and at last follow-up were similar between cases and controls except for subgroup of patients with pre-transplant POx >30mcmol/L where 1-year eGFR was lower compared to controls. Across eGFR categories, more cases were in eGFR category <30ml/min/1.73m2 compared to controls.

DISCUSSION/CONCLUSION

Roux-en-Y gastric bypass is the most common identifiable risk for elevated POx in kidney transplant candidates. 1-year graft function was not inferior in cases compared to matched controls except for subgroup with POx>30mcmol/L pre-transplant.

Design of digital image encryption based on elliptic curve cryptography (ECC) algorithm and Radix-64 conversion

The billions of bits of information are transferred each second through the internet every day. The information may be text, image, audio or video etc, accordingly, we need some protection mechanism while sharing confidential data. Generally, RSA algorithm is used for encrypting the Secret images. However, the security provided by Elliptic Curve Cryptography (ECC) is higher with lower sized key than the RSA algorithm. So, this article proposes an extended Elliptic Curve encryption approach for encrypting the secret images. In this system, the secret image is partitioned into three color image planes such as Red, Green and Blue. By applying Radix-64 encoding and Mapping table, these planes are converted into elliptic curve points and then these points are encrypted using ECC algorithm. Again, these points are applied to the Radix-64 decoding and the mapping table to get ciphered-image. At last, the key parameters such as a, b, p and Generator point (G) are embedded in the last four pixel positions of the ciphered-image. In order to get the original secret image, the recipient must extract these key parameters from the encrypted image and then apply the remaining processes to the encrypted image in the opposite order. Experimental results tested using MATLAB R2021b and it shows that the NPCR and UACI values are 99.54% and 28.73 % and better quality feature is attained since the entropy value is almost closer to eight. So, the proposed image encryption has robust capacity to fight against the differential attack.

Concomitant pulmonary disease is common among patients with extrapulmonary TB

BACKGROUND :

Microbiologic screening of extrapulmonary TB (EPTB) patients could inform recommendations for aerosol precautions and close contact prophylaxis. However, this is currently not routinely recommended in India. Therefore, we estimated the proportion of Indian patients with EPTB with microbiologic evidence of pulmonary TB (PTB).

METHODS :

We characterized baseline clinical, radiological and sputum microbiologic data of 885 adult and pediatric TB patients in Chennai and Pune, India, between March 2014 and November 2018.

RESULTS :

Of 277 patients with EPTB, enhanced screening led to the identification of 124 (45%) with concomitant PTB, including 53 (19%) who reported a cough >2 weeks; 158 (63%) had an abnormal CXR and 51 (19%) had a positive sputum for TB. Of 70 participants with a normal CXR and without any cough, 14 (20%) had a positive sputum for TB. Overall, the incremental yield of enhanced screening of patients with EPTB to identify concomitant PTB disease was 14% (95% CI 12–16).

CONCLUSIONS :

A high proportion of patients classified as EPTB in India have concomitant PTB. Our results support the need for improved symptom and CXR screening, and recommends routine sputum TB microbiology screening of all Indian patients with EPTB.

The effect of radiological imaging on treatment delay and hospitalisation in patients with peritoneal dialysis-related peritonitis: A secondary analysis of the PROMPT study

BACKGROUND

In peritoneal dialysis-related peritonitis (peritonitis), delayed antibiotic therapy is associated with adverse outcomes. Identifying barriers to timely treatment may improve outcomes.

AIM

To determine the impact of radiological investigations on treatment delay and predictors of hospitalisation and length of stay (LOS).

METHODS

Retrospective review of patients with presumed peritonitis in Western Australia.

RESULTS

In 153 episodes of peritonitis, 79 (51.6%) resulted in admission with a median LOS of 3 days (Q1, Q3: 1, 6). In a multivariable model, significant predictors of admission were abnormal exit-site (odds ration (OR) 5.7; 95% confidence interval (CI): 1.4, 23.6; p = 0.02), failure to detect a cloudy bag (OR 11.9; 95%CI: 3.2, 44.7; p < 0.001), female sex (OR 3.3; 95% CI: 1.4, 9.7; p = 0.027), radiological imaging within 24 h (OR 8.8; 95% CI: 2.2, 34.8; p = 0.002) and contact with ambulant care facility (OR 0.32, 95% CI: 0.11, 0.98; p = 0.04). Imaging within 24 h of presentation occurred in 41 (27%) episodes of peritonitis, mostly plain X-rays (91%), of which 83% were clinically irrelevant. Imaging performed within 24 h of presentation increased the median time to antibiotic treatment (2.9 h (Q1, Q3: 1.6, 6.4) vs 2.0 h (Q1, Q3: 1, 3.8; p = 0.046)). Imaging performed prior to administering antibiotics significantly increased the median time to treatment (4.7 h (Q1, Q3: 2.9, 25) vs 1.5 h (Q1, Q3: 0.75, 2.5; p < 0.001)) in those where imaging followed antibiotic treatment.

CONCLUSIONS

Half of all presentations with peritonitis result in hospital admission. Radiological imaging was associated with an increased risk of hospitalisation, potentially contributes to treatment delay, and was mostly clinically unnecessary. When required, imaging should follow antibiotic therapy.

Chronic Kidney Disease of Undetermined Etiology around the World

BACKGROUND

Epidemics of chronic kidney disease of uncertain etiology (CKDu) are occurring on the Pacific coast of Central America, in Sri Lankan and Indian agricultural communities, and in other hotspots around the world. CKDu primarily affects male agricultural workers, and traditional risk factors such as diabetes and hypertension are not involved in the pathogenesis. Although a causal factor has not yet been identified, culprits include repeated volume depletion-induced kidney injury, as well as exposure to agrichemicals, heavy metals and nephrotoxins contained in drugs, beverages, and traditional medications. Multiple risk factors may interact in a synergistic fashion thus resulting in chronic kidney damage. The absence of undefined protective factors may amplify the risk.

SUMMARY

This review focuses on the current understanding of CKDu by analyzing epidemiology, potential risk factors, and clinical and pathological features as well as geographical peculiarities of each disease. We also focus our attention on the etiology of these conditions in which multiple factors may synergistically contribute to the development and progression of the disease. The last part of the manuscript is dedicated to the research agenda and practical recommendations. Key Messages: Since renal replacement therapy is not extensively available in areas where CKDu is widespread, prevention by avoiding all known potential risk factors is crucial. Innovative healthcare solutions and social policies in endemic areas along with collaborative clinical research projects are needed to better identify factors involved in disease promotion and progression.

Protective role of DJ-1 in endotoxin-induced acute kidney injury

Acute kidney injury (AKI) is a frequent complication of sepsis and an important cause of morbidity and mortality worldwide. A cornerstone of sepsis-associated AKI is dysregulated inflammation, leading to increased tissue oxidative stress and free radical formation, which leads to multiple forms of cell death. DJ-1 is a peroxiredoxin protein with multiple functions, including its ability to control cellular oxidative stress. Although DJ-1 is expressed prominently by renal tubules, its role in AKI has not been investigated. In the present study, we examined the effect of DJ-1 deficiency in a murine model of endotoxin-induced AKI. Endotoxemia induced greater kidney injury in DJ-1-deficient mice. Furthermore, DJ-1 deficiency increased renal oxidative stress associated with increased renal tubular apoptosis and with expression of death domain-associated protein (DAXX). Similar to the in vivo model, in vitro experiments using a medullary collecting duct cell line (mIMCD3) and cytotoxic serum showed that serum obtained from wild-type mice resulted in increased expression of s100A8/s100A9, DAXX, and apoptosis in DJ-1-deficient mIMCD3 cells. Our findings demonstrate a novel renal protective role for renal tubular DJ-1 during endotoxemia through control of oxidative stress, renal inflammation, and DAXX-dependent apoptosis.

FRI0011 DEVELOPMENT OF A HIGH-DIMENSIONAL FLOW CYTOMETRY PANEL TO ANALYSE NATURAL KILLER CELLS IN SLE

Background:

Natural Killer (NK) cells are an innate immune cell type that has somewhat been overlooked in the context of systemic lupus erythematosus (SLE). SLE patients display a reduced number of NK cells with an activated phenotype and increased capacity to produce IFN-γ, decreased antibody-dependent cellular cytotoxicity (ADCC), and altered natural cytotoxicity (1). NK cell activation is determined by the integration of input from a myriad of activating and inhibitory receptors. Previously, using Nanostring® gene expression technologies, we found our SLE cohort showed decreased gene expression of a number of these receptors (KLRC2, KLRC1, KLRB1, KLRF1, KLRG1, PRF1 and IL2RB) leading us to explore NK cells in SLE in more depth.

Objectives:

Our aim was to develop a high-dimensional flow cytometry panel to characterise dysregulation of NK cell in SLE, with particular reference to the activating and inhibitory receptors found to be dysregulated in SLE at the gene expression level.

Methods:

Markers for NK panel were selected to include canonical phenotyping/functional molecules of NK cells with a particular emphasis on receptors found to be lower in our SLE cohort’s gene expression findings. NK panel was designed to minimise spectral overlap, expression and co-expression of markers was taken into consideration. Antibodies were titrated, and voltages optimised to achieve the best separation index for each of the antibodies. The 24-marker panel was run on 52 SLE patients of various disease manifestations, treatments and disease severity. 20 healthy controls were also run for comparison.

Results:

A 24-marker flow cytometry panel including 19 NK cell antigens was optimised, including basic phenotype (CD3/CD56/CD16/NKp46) and NK differentiation markers (CD57/CD94), activating and inhibitory receptors (NKG2A/NKG2C/NKG2D), costimulatory receptors (CD244/CD226), transcription factors (Eomes/Tbet) and effector molecules (granzyme/perforin). Immunophenotypic high-parameter analysis of SLE and control samples is in progress and results will be presented.

Conclusion:

Our development of a high-dimensional immunophenotypic panel allows identification of changes in NK cells in SLE including antigen expression levels, subset percentages and potentially of novel subsets. This panel will be used to investigate NK cell changes with disease course/activity, therapeutic response, and to discover potential drug targets for SLE.

References:

[1]Spada R, Rojas JM, Barber DF. Recent findings on the role of natural killer cells in the pathogenesis of systemic lupus erythematosus. J Leukocyte Biol. 2015;98(4):479-487. doi:10.1189/jlb.4ru0315-081rr

Acknowledgments:

Westmead Institute for Medical Research Genomics Facility

Westmead Institute for Medical Research Flow Cytometry Facility

Staff Specialists’ TESL and Trust Fund Committee

Disclosure of Interests:

None declared

Therapeutic Benefit of Regulating Iron Metabolism in Spontaneous Lupus Nephritis

Background

Lupus nephritis (LN) is an end-organ complication of Systemic lupus erythematosus and is more common in premenopausal women. Hepcidin, the master regulator of iron homeostasis, modulates inflammation and is negatively regulated by estrogen. Therefore, we hypothesized that exogenous hepcidin may reduce the severity and delay the onset of LN.

Methods

Pre-nephritic 8-week-old or nephritic 16-week-old MRL/lpr female mice were injected Hepcidin (50ug, i.p) or vehicle twice a week and markers of renal injury and inflammation were examined at 18 and 20 weeks of age. The direct effect of hepcidin on macrophages was studied in-vitro.

Results

Hepcidin reduced intrarenal iron accumulation, and increased H-ferritin. This was associated with reduced renal inflammation and immune cell infiltration, which collectively mitigated microalbuminuria and tubular injury, independent of immune complex deposits and autoantibodies. The increase in H-ferritin, was associated with a reduced number of renal Ki-67+-F4/80+ macrophages. In-vitro, hepcidin induced H-ferritin in macrophages and reduced labile (Fe2+) iron. H-ferritinhi macrophages proliferated less upon Mcsf-1 stimulation and secreted less IL-1b, and IL-6 upon TLR-3 activation. Hepcidin reduced microalbuminuria when administered to nephritic, 16-week-old mice without worsening lupus-associated anemia.

Conclusions

We have identified that hepcidin targets iron homeostasis and reduces cardinal pathogenic features of LN. Importantly, Hepcidin treatment ameliorates kidney disease in mice with established proteinuria. Thus, our data highlight that targeting cellular iron metabolism with hepcidin represents a promising and a new therapeutic strategy in LN.

Safety and tolerability of injectable Rilpivirine LA in HPTN 076: A phase 2 HIV pre-exposure prophylaxis study in women

BACKGROUND

Daily oral TDF/FTC is protective against HIV infection when used for pre-exposure prophylaxis (PrEP). However, daily adherence to oral PrEP is difficult for many; therefore, finding alternative PrEP strategies remains a priority. HPTN 076 evaluated the long-acting injectable form of rilpivirine (RPV), known as RPV LA for safety, pharmacokinetics and acceptability.

METHODS

HPTN 076 (NTC 02165202) was a phase 2, double-blind, 2:1 randomized trial comparing the safety of 1200mg RPV LA (LA) to placebo (P). The study included a 28-day oral run-in phase of daily, self- administered oral RPV (25 mg), with directly observed oral dosing about six times. Of 136 enrolled sexually active, HIV-uninfected, low HIV-risk African (100) and US (36) adult women, injectable product was administered in two gluteal, intramuscular (IM) injections once every eight weeks to 122 participants following the oral run-in phase. A maximum of six injection time points occurred over a 48-week period. Acceptability, safety, tolerability and pharmacokinetic (PK) data were collected throughout the study. This paper includes primary endpoint data collected up to the week 52 post enrollment.

FINDINGS

The median age of the enrolled population was 31 years (IQR: 25,38), median weight 75 kg (IQR: 64, 89), median body mass index (BMI) 30 (IQR: 27, 35), 46% married, 94% Black and 60% unemployed. A total of 122 (80 LA, 42 P) women received at least one injection and 98 (64 LA, 34 P) received all six injections. During the injection phase, three women withdrew from the study (2 LA, 1 P) and 16 women discontinued study product (10 LA, 6 P). Fourteen women (11 LA and 3 P) discontinued oral study product and did not enter the injection phase. Study product discontinuations were not significantly different between the two arms throughout. Of the product discontinuations in the injection phase, 8% in LA and 5% in P arm were due to adverse events (AEs), including one randomized to the P arm with prolonged QTc interval on EKG. The proportion of women who experienced Grade 2 or higher AEs during the injection phase as the primary outcome was not significantly different between the two arms [73.8%, 95% CI: (63.2%, 82.1%) for LA and 73.8%, 95% CI: (58.9%, 84.7%), p>0.99]. Transient Grade ≥2 liver abnormalities occurred in 14% of women in the LA arm compared with 12% in P arm. Three LA women (4%) developed Grade 3 injection site reactions compared with none in P arm. In participants who received at least 1 injection, the geometric mean of overall RPV trough concentrations (Ctrough) was 62.2 ng/mL. In participants who received all six injections, the geometric mean of CTrough through the injection phase and after the last injection were 72.8 ng/mL and 100.9 ng/mL, respectively. At week 52 (eight weeks after last injection), the geometric mean of RPV Ctrough was 75.0 ng/mL. At the last injection visit (Week 44), 80 % of women who answered acceptability questions strongly agreed that they would think about using- and 68% that they would definitely use a PrEP injectable in the future.

INTERPRETATION

RPV LA IM injections every eight weeks in African and US women were safe and acceptable. Overall, despite more injection site reactions and pain in the participants receiving RPV LA the injections were well tolerated. Data from this study support the further development of injectable PrEP agents.

Modulation of iron homeostasis with hepcidin ameliorates spontaneous murine lupus nephritis

Lupus nephritis is the end organ manifestation of systemic lupus erythematosus. Iron metabolism and its master regulator, hepcidin, are known to regulate cell proliferation and inflammation, but their direct role in the pathophysiology of lupus nephritis remains under-investigated. Exogenous hepcidin reduced the severity of lupus nephritis in MRL/lpr mice, a preclinical model of spontaneous systemic lupus erythematosus without worsening anemia of inflammation. Hepcidin treatment reduced renal iron accumulation, systemic and intrarenal cytokines, and renal immune cell infiltration, independent of glomerular immune complex deposits and circulating autoantibodies. Hepcidin increased renal H-ferritin (a ferroxidase), reduced expression of free iron dependent DNA synthesis enzymes, Ribonucleotide Reductase 1 and 2, and intra-renal macrophage proliferation. These findings were recapitulated in vitro upon treatment of macrophages with hepcidin and murine colony stimulation factor-1. Furthermore, hepcidin-treated macrophages secreted less IL-1β and IL-6 upon stimulation with the TLR3 agonist polyinosine-polycytidylic acid. Of clinical relevance, hepcidin reduced progression and severity of nephritis in old mice with established systemic autoimmunity and overt proteinuria, highlighting its therapeutic potential. Thus, our findings provide a proof-of-concept that targeting cellular iron metabolism with hepcidin represents a promising therapeutic strategy in lupus nephritis.

Pharmacokinetics of rifampicin in adult TB patients and healthy volunteers: a systematic review and meta-analysis

Objectives

The objectives of this study were to explore inter-study heterogeneity in the pharmacokinetics (PK) of orally administered rifampicin, to derive summary estimates of rifampicin PK parameters at standard dosages and to compare these with summary estimates for higher dosages.

Methods

A systematic search was performed for studies of rifampicin PK published in the English language up to May 2017. Data describing the C_max and AUC were extracted. Meta-analysis provided summary estimates for PK parameter estimates at standard rifampicin dosages. Heterogeneity was assessed by estimation of the I² statistic and visual inspection of forest plots. Summary AUC estimates at standard and higher dosages were compared graphically and contextualized using preclinical pharmacodynamic (PD) data.

Results

Substantial heterogeneity in PK parameters was evident and upheld in meta-regression. Treatment duration had a significant impact on the summary estimates for rifampicin PK parameters, with C_max 8.98 mg/L (SEM 2.19) after a single dose and 5.79 mg/L (SEM 2.14) at steady-state dosing, and AUC 72.56 mg·h/L (SEM 2.60) and 38.73 mg·h/L (SEM 4.33) after single and steady-state dosing, respectively. Rifampicin dosages of at least 25 mg/kg are required to achieve plasma PK/PD targets defined in preclinical studies.

Conclusions

Vast inter-study heterogeneity exists in rifampicin PK parameter estimates. This is not explained by the available modifying variables. The recommended dosage of rifampicin should be increased to improve efficacy. This study provides an important point of reference for understanding rifampicin PK at standard dosages as efforts to explore higher dosing strategies continue in this field.

Diabetes and pre-diabetes among household contacts of tuberculosis patients in India: is it time to screen them all?

SETTING

Pre-diabetes mellitus (pre-DM) and DM increase the risk of developing tuberculosis (TB). Screening contacts of TB patients for pre-DM/DM and linking them to care may mitigate the risk of developing TB and improve DM management.

OBJECTIVE

To measure the prevalence of pre-DM/DM and associated factors among the adult household contacts (HHCs) of pulmonary TB patients.

METHODS

Between August 2014 and May 2017, adult HHCs of newly diagnosed adult PTB patients in Pune and Chennai, India, had single blood samples tested for glycosylated haemoglobin (HbA1c) at enrolment. DM was defined as previously diagnosed, self-reported DM or HbA1c 6.5%, and pre-DM as HbA1c between 5.7% and 6.4%. Latent tuberculous infection (LTBI) was defined as a positive tuberculin skin test (5 mm induration) or QuantiFERON® Gold In-Tube (0.35 international units/ml).

RESULTS

Of 652 adult HHCs, 175 (27%) had pre-DM and 64 (10%) had DM. Forty (64%) HHCs were newly diagnosed with DM and 48 (75%) had poor glycaemic control (HbA1c 7.0%). Sixty-eight (22%) pre-DM cases were aged 18-34 years. Age 35 years, body mass index 25 kg/m2, chronic disease and current tobacco smoking were significantly associated with DM among HHCs.

CONCLUSIONS

Adult HHCs of TB patients in India have a high prevalence of undiagnosed DM, pre-DM and LTBI, putting them at high risk for developing TB. Routine DM screening should be considered among all adult HHCs of TB.

Protective Role of Hepcidin in Polymicrobial Sepsis and Acute Kidney Injury

Background: Acute kidney injury (AKI) portends worse prognosis following sepsis, with limited available interventions. Host iron acquisition by pathogens and systemic inflammatory response are key events in the pathogenesis of sepsis. In sepsis, hepcidin induces iron sequestration to limit iron availability to pathogens. Hepcidin is also known to limit inflammation. Since its role in pathophysiology of sepsis-associated AKI is unknown, we investigated the effect of exogenous hepcidin in endotoxin- and peritonitis-induced pathology and AKI.

Methods: C57BL/6 mice were treated with saline or 50–100 µg of hepcidin, pre- and post-LPS injection, or cecal ligation and puncture (CLP, model of peritonitis). Splenectomized mice were challenged with LPS, with and without hepcidin. Mice were euthanized at 24 h after LPS injection and at different time points after CLP. Systemic inflammation and renal injury markers were assessed. Direct effect of hepcidin on renal tubular and endothelial cells was evaluated using endotoxin-induced cytotoxic serum. Role of heavy chain ferritin (H-ferritin) in mediating hepcidin-induced anti-inflammatory effect on LPS stimulated macrophages was evaluated with siRNA studies.

Results: Twenty-four hours pretreatment with hepcidin significantly reduced LPS-induced AKI. Hepcidin ameliorated LPS-induced increase in serum TNFα and renal Cox-2, and prevented loss in PGC1α and cytochrome c oxidase activity. This was associated with reduced glomerular injury and preserved mitochondrial structure. Hepcidin did not exert direct protection on the renal parenchymal cells but reduced endotoxin-induced serum cytotoxicity to mitigate renal injury. Splenectomy reduced LPS-induced early inflammation and AKI, independent of hepcidin, indicating the importance of systemic inflammation. Higher splenic H-ferritin in hepcidin-treated animals was associated with reduced splenocytes apoptosis and inflammation. Hepcidin reduced LPS-induced IL-6 secretion in macrophages in H-ferritin dependent manner. Hepcidin significantly reduced CLP-induced AKI, and mortality (20% hepcidin treated vs 80% PBS treated). Importantly hepcidin reduced bacteremia and AKI even when administered after onset of sepsis.

Conclusion: We demonstrate a protective role of hepcidin in endotoxin- and peritonitis-induced pathologies and AKI, exerted primarily through its anti-inflammatory effects, and antibacterial property. Macrophage H-ferritin plays an important role in hepcidin-mediated protection against endotoxin-induced inflammation. We uncover a novel prophylactic and therapeutic role of hepcidin in sepsis-associated bacteremia, AKI, and mortality.

Iron Homeostasis Pathways as Therapeutic Targets in Acute Kidney Injury

BACKGROUND

Iron is critical for fundamental biologic functions such as cell division and mitochondrial electron transport. However, by the virtue of its ability to donate electrons, iron is probably the most effective oxidant in biologic systems.

SUMMARY

To avoid damage from iron-mediated oxidative injury or ferroptosis, multiple defense mechanisms exist including iron binding proteins and robust glutathione-dependent intracellular pathways. Hepcidin, through its ability to sequester iron within macrophages and induce H-ferritin, serves as an endogenous protective molecule against ferroptosis. Key Messages: Recent studies have demonstrated the protective role of hepcidin in both ischemic reperfusion injury and heme-mediated models of acute kidney injury (AKI). Ferroptosis-inhibiting drugs and hepcidin offer exciting novel prospects to treat AKI.

Alcohol intervention strategy among tuberculosis patients: a pilot study from South India

BACKGROUND

Alcohol dependence has been a major cause of treatment non-adherence in tuberculosis (TB) management. There is an urgent need to develop a feasible, acceptable alcohol intervention programme to ensure treatment completion.

METHODOLOGY

Four of the 10 Chennai Corporation zones in Chennai, South India, were randomly selected: two each for the experimental and control arms of the study. TB patients registered from August 2013 to January 2014 with the Revised National Tuberculosis Control Programme were assessed using the Alcohol Use Disorder Identification Test (AUDIT) scale. The intervention consisted of four individual counselling sessions at months 0, 2, 4 and 6 conducted by highly trained interventionists.

RESULTS

Of 872 TB patients, 298 (31%) were found to have alcohol use disorders. The numbers of TB patients in the experimental and control arms were respectively 113 (38%) and 185 (62%). The proportion of patients with favourable treatment outcomes was higher in the intervention than in the control group (87% vs. 62%, P = 0.04). Overall adherence to anti-tuberculosis treatment was significantly higher in the intervention group (P = 0.02).

CONCLUSION

Study findings suggest that alcohol interventions could be effective in ensuring favourable TB treatment outcomes and adherence. This calls for a large cluster randomised trial for greater generalisability. Tested alcohol-intervention strategies should be recommended to promote treatment adherence among TB patients who consume alcohol.

Factors associated with sputum culture conversion in multidrug-resistant pulmonary tuberculosis

INTRODUCTION

Sputum culture conversion in pulmonary multidrug-resistant tuberculosis (MDR-TB) is important to make treatment-related decisions and prevent transmission of disease.

OBJECTIVE

To identify factors associated with sputum culture conversion, and to determine time to culture conversion and the impact of culture conversion on successful treatment outcomes in MDR-/rifampicin (RMP) resistant TB.

METHOD

Retrospective analysis of data from treatment cards and registers of MDR-/RMP-resistant patients initiated on treatment under India's Revised National TB Control Programme in Delhi, West Bengal and Kerala from January 2009 to December 2011. Proportions were calculated and logistic regression analysis was performed.

RESULTS

Of 836 patients, 787 were analysed, 651 (83%) of whom experienced culture conversion: respectively 57%, 73% and 79% culture converted by month 3, 4 and 6 of treatment. The median time to culture conversion was 91.3 days. Patients with body mass index (BMI) 16 kg/m2 (OR 0.403, P = 0.001) and 1618 kg/m2 (OR 0.519, P = 0.039) were less likely to have culture conversion. High rates of culture conversion were observed in patients with successful treatment outcomes compared to those without treatment success (462/469, 99% vs. 183/311, 59%; P 0.0001).

CONCLUSION

Low BMI is associated with poor sputum culture conversion in MDR-/RMP-resistant TB patients. Lack of culture conversion can impact successful treatment outcomes.

Pharmacokinetics of thrice-weekly rifampicin, isoniazid and pyrazinamide in adult tuberculosis patients in India

OBJECTIVE

To study the pharmacokinetics of rifampicin (RMP), isoniazid (INH) and pyrazinamide (PZA) in adult tuberculosis (TB) patients and examine factors that influence drug pharmacokinetics.

METHODS

Adult TB patients (n = 101) receiving thrice-weekly anti-tuberculosis treatment in the Revised National TB Control Programme (RNTCP) were studied. The study was conducted at steady state after directly observed drug administration. RMP, INH and PZA concentrations were estimated using high-performance liquid chromatography and NAT2 genotyping by real-time polymerase chain reaction.

RESULTS

RMP peak concentration (Cmax) was sub-therapeutic (<8 μg/ml) in 88% of the patients. The Cmax of RMP, INH and PZA at 2 h was observed in respectively 83.2%, 97.0% and 92.1% of the patients. The Cmax and area under the curve from 0 to 8 h (AUC0-8) of PZA was lower in TB patients with diabetes mellitus than in non-diabetics. Significant associations were observed between the Cmax and the AUC0-8 of RMP, INH and PZA with drug doses; RMP with category of treatment; INH with smoking, body mass index and N-acetyl transferase 2 genotype; and PZA with sex and smoking.

CONCLUSIONS

Several risk factors for drug concentration variations were identified. Two-hour post-dosing drug concentrations mimicked Cmax. A high proportion of TB patients had RMP Cmax below the expected range, which is a matter of concern.

Treatment outcomes of daily anti-tuberculosis treatment in HIV-infected patients seeking care at a private clinic in India

SETTING

Little is known about outcomes of patients co-infected with human immunodeficiency virus (HIV) and tuberculosis (TB) who are treated in the private sector in India.

OBJECTIVE

To describe the treatment outcomes of daily anti-tuberculosis treatment (ATT) and their determinants among HIV-TB co-infected patients treated at a private clinic in Pune, India.

DESIGN

Data on adult HIV-TB co-infected patients treated with daily ATT were analysed using logistic regression and Cox model to assess risk factors for default and death.

RESULTS

Of 769 cases, 78% were aged <45 years, 71% were males, 64% had CD4 < 200 cells/mm³, 67% were antiretroviral treatment (ART) naïve at TB diagnosis, 53% had extra-pulmonary TB, and 12% had a past history of TB. ATT was successfully completed by 58.5%, 34.3% defaulted (i.e., discontinued ATT for >2 months) and 3.9% died during ATT. The risk of default was higher among males (aOR 1.67, 95%CI 1.17-2.39), ART-naïve patients (aOR 1.91, 95%CI 1.34-2.73) and those with a past history of TB (aOR 1.86, 95%CI 1.15-3.01). Survival probability at 365 days was 95% (95%CI 93-97). The risk of death was higher among patients with CD4 < 50 cells/mm³ (aHR 4.63, 95%CI 1.47-14.65) than in those with CD4 > 200 cells/mm³.

CONCLUSIONS

Low overall mortality was seen with daily ATT in HIV-TB co-infected patients. High default rates in private facilities warrant urgent attention.

TB-HIV co-infection: a catastrophic comradeship

The symbiotic association of tuberculosis (TB) and HIV poses a challenge to human survival. HIV complicates every aspect of TB including presentation, diagnosis and treatment. HIV-TB patients encounter unique problems like drug-drug interactions, cumulative toxicity, immune reconstitution inflammatory syndrome (IRIS), lower plasma drug levels and emergence of drug resistance during treatment despite adherence. TB may also be overdiagnosed in HIV due to a number of diseases that closely resemble TB. Notable among them are non-tuberculous mycobacteria, Pneumocystis Jirovecii and Nocardia. Even though diagnostic procedures have improved over the years, patients in developing countries usually seek health care at later stage of the disease. Research data ascertains the duration of therapy for TB to be 6 months with rifampicin and isoniazid, reinforced with ethambutol and pyrazinamide in the first 2 months. The schedule of therapy is still debatable with daily regimens being preferred in the context of HIV. Many reasons exist for persistence of Mycobacterium Tuberculosis (M.TB) in sputum, or delayed-clearance of TB from sputum smears in HIV, apart from emergence of drug resistance and non-compliance. Acquired rifampicin resistance (ARR) is a unique phenomenon complicating HIV-associated TB when an intermittent regimen of antituberculosis therapy (ATT) is used without timely initiation of highly active antiretroviral therapy (HAART), especially in patients harbouring isoniazid-resistant strains Immune restoration is often incomplete ('swiss cheese' pattern) even with effective HAART if not started early. Immune reconstitution inflammatory syndrome (IRIS) is the paradoxical worsening of the patient's condition often with radiological deterioration, due to an enhanced immune response with HAART. IRIS occurs despite an effective virological suppression and a favourable response to ATT. The incidence of IRIS in HIV has reached up to 54%, requiring utilization of experts and tertiary care which forms an obstacle to the decentralization of patients in the ART programme. Research in HIV-TB immunology and management needs further exploration in order to understand the diseases and offer appropriate treatment. The following paragraphs provide scientific evidences generated through research that could potentially guide management.

Loss to follow-up among children in pre-ART care under the National AIDS Programme, Tamil Nadu, South India

Setting: Children aged <15 years constitute 7% of all people living with the human immunodeficiency virus (HIV) in India. A previous study from an antiretroviral therapy (ART) centre in south India reported 82% loss to follow-up (LTFU) among children in pre-ART care (2006-2011). Objective: To assess the proportion of LTFU within 1 year of registration among HIV-infected children (aged < 15 years) registered in all 43 ART centres in the state of Tamil Nadu, India, during the year 2012. Design: This was a retrospective cohort study involving a review of programme records. Results: Of 656 children registered for HIV care, 20 (3%) were not assessed for ART eligibility. Of those remaining, 226 (36%) were not ART eligible and entered pre-ART care. Among these, at 1 year of registration, 50 (22%) were LTFU, 40 (18%) were transferred out and 136 (60%) were retained in care at the same centre. The child's age, sex, World Health Organization stage or occurrence of opportunistic infection were not associated with LTFU. Conclusion: One in five children registered under pre-ART care were lost to follow-up. Stronger measures to prevent LTFU and reinforce retrieval actions are necessary in the existing National HIV Programme.

Role of bacille Calmette-Guérin in preventing tuberculous infection

SETTING

Rural community in South India.

OBJECTIVE

To determine the role of bacille Calmette-Guérin (BCG) in preventing tuberculous infection in children.

DESIGN

A prevalence survey was undertaken in 1999-2001 in a representative rural population in Tiruvallur District in South India using cluster sampling. Tuberculin testing was performed among all children aged <15 years, and all adults aged 15 years were questioned about chest symptoms and underwent radiography, followed by sputum examinations, if indicated.

RESULTS

In children living in households with a tuberculosis case, the proportion with evidence of tuberculous infection was 35.5% of 200 in the absence of a BCG scar and 27.0% of 100 in its presence, a reduction of 24% (P = 0.14). In very young children (age <5 years), the corresponding proportions were 29.1% of 55 and 11.9% of 42, a reduction of 59%; the difference was statistically significant (P = 0.048).

CONCLUSION

There is a possible role for BCG in preventing tuberculous infection in very young children.

Predictors of unfavourable treatment outcome in patients with multidrug-resistant tuberculosis in India

Setting: India has one of the highest global rates of multidrug-resistant tuberculosis (MDR-TB), which is associated with poor treatment outcomes. A better understanding of the risk factors for unfavourable outcomes is needed. Objectives: To describe 1) the demographic and clinical characteristics of MDR-TB patients registered in three states of India during 2009-2011, 2) treatment outcomes, and 3) factors associated with unfavourable outcomes. Design: A retrospective cohort study involving a record review of registered MDR-TB patients. Results: Of 788 patients, 68% were male, 70% were aged 15-44 years, 90% had failed previous anti-tuberculosis treatment or were retreatment smear-positive, 60% had a body mass index < 18.5 kg/m² and 72% had additional resistance to streptomycin and/or ethambutol. The median time from sputum collection to the start of MDR-TB treatment was 128 days (IQR 103-173). Unfavourable outcomes occurred in 40% of the patients, mostly from death or loss to follow-up. Factors significantly associated with unfavourable outcomes included male sex, age ⩾ 45 years, being underweight and infection with the human immunodeficiency virus. Adverse drug reactions were reported in 24% of patients, with gastrointestinal disturbance, psychiatric morbidity and ototoxicity the most common. Conclusion: Long delays from sputum collection to treatment initiation using conventional methods, along with poor treatment outcomes, suggest the need to scale up rapid diagnostic tests and shorter regimens for MDR-TB.

Physician's advice on quitting smoking in HIV and TB patients in south India: a randomised clinical trial

Setting: National Institute for Research in Tuberculosis, Madurai, India. Objective: To determine the efficacy of physician's advice on quitting smoking compared with standard counselling in patients with tuberculosis (TB) and patients with human immunodeficiency virus (HIV) infection. Design/Methods: This was a clinical trial conducted in Madurai, south India, among 160 male patients (80 with TB and 80 with HIV), randomised and stratified by nicotine dependence (low/high according to the Fagerström scale), who received physician's advice with standard counselling or standard counselling alone for smoking cessation. Abstinence at 1 month was assessed by self-report and carbon monoxide breath analysis. Results: The patients' mean age was 39.4 years (SD 8.5). Overall, 35% of the patients had high nicotine dependence. Most patients (41%) smoked both cigarettes and bidis. In a combined analysis including both the HIV and the TB groups, quit rates were 41% of the 68 patients in the physician group and 35% of the 68 patients in the standard counselling arm. Conclusions: Physician's advice to quit smoking delivered to patients with TB or HIV is feasible and acceptable. Smoking cessation could easily be initiated in TB patients in programme settings. Future studies should assess long-term abstinence rates with a larger sample size to demonstrate the efficacy of physician's advice.

Pancreatic Tuberculosis: A Puzzle for Physicians. A Rare Case and Review of Literature

Pancreatic Tuberculosis is an uncommon form of extra pulmonary tuberculosis that resembles malignancy of pancreas and serve as a diagnostic challenge for physicians. Conservative management with Anti Tuberculosis Therapy (ATT) will suffice for pancreatic tuberculosis whereas a malignancy may require major surgeries which may lead to significant morbidity. Here, we discuss the case of a female patient who presented with abdominal pain and vomiting and is a known case of chronic calcific pancreatitis. Radiological findings were that of malignancy of the pancreas. Enteroscopy showed pus flowing out from the duodenum. Endoscopic Ultrasound (EUS) guided Fine Needle Aspiration Cytology (FNAC) of the pancreas revealed acid fast bacilli. The patient was treated successfully with ATT. Timely diagnosis of this rare form of extra pulmonary tuberculosis can thus help avoid unwanted resections done for presumed malignancy, for which a high index of suspicion is needed.

Treatment of childhood tuberculosis in India

With a quarter of the global burden of tuberculosis (TB) occurring in India, children in this country are at high risk of tuberculous infection and TB disease. India's Revised National Tuberculosis Control Programme provides free diagnosis and treatment for children with TB using quality assured, weight-based individual drug boxes. Guidelines have recently been revised, updating both the diagnostic algorithm and shifting to a daily regimen with World Health Organization recommended dosages using child-friendly, fixed-dose combination pills. Active case finding is practised in households of TB patients as well as among human immunodeficiency virus infected and malnourished children. More attention needs to be paid to the provision of preventive therapy for household contacts aged <6 years as well as to the detection of multidrug-resistant TB among children. Case notification and the use of the Standards of TB Care in India are being strengthened in the private sector.

Gadolinium toxicity: Iron and ferroportin as central targets

Gadolinium-based magnetic resonance (MR) contrast agents (GBCM) causes a devastating systemic fibrosing illness, nephrogenic systemic fibrosis (NSF), in patients with reduced kidney function. GBCM targets iron-recycling CD163- and ferroportin-expressing macrophages to release labile iron that mediates gadolinium toxicity and NSF. GBCA might similarly target iron-rich, ferroportin-expressing structures such as globus pallidus and cerebellar dentate nucleus in the brain to result in metal accumulation and potential toxicity.

Tuberculosis mortality in a rural population from South India

BACKGROUND

General mortality rate (GMR) is an essential indicator for assessing the health status of a community. Tuberculosis (TB) mortality is an indicator for the Millennium Development Goal for 2015.

METHODS

This community-based retrospective survey was conducted in 2007-2008 on a sample of 114,605 rural populations living in 56 villages randomly selected from 218 villages in Tiruvallur district, South India, where the DOTS strategy was implemented in 1999. All the permanent residents of the households were registered and information on occurrence of death was recorded. All the deaths were investigated by verbal autopsy (VA) using standardized methods.

RESULTS

A total of 719 deaths were registered. The GMR and tuberculosis mortality rate (TMR) were 648 (95% CI: 568-727) and 39 (95% CI: 25-52) per 100,000 p-yrs, respectively. The GMR increased with age, and was higher in males than females at all ages. The TMR was higher in males than females and the overall male:female ratio was 5:1.

CONCLUSION

TB was the 6th leading cause of death overall and the 2nd leading cause among men in this area. Strategies to reduce TB death should be implemented and the impact should be monitored by repeat VA studies.

General and tuberculosis mortality in two states of India: A population-based survey

BACKGROUND

General and cause-specific mortality data for causes of death are not available for the states of Andhra Pradesh (AP) and Orissa in India.

OBJECTIVES

To estimate general mortality rate (GMR) and the tuberculosis mortality rate (TMR) among the general population in the two states.

METHODS

All permanent residents in households of selected districts of AP and Orissa states were registered in the survey in 2005-2006. A sample size of 380,000 persons was selected from each state. Health workers carried out house-to-house enumeration. Demographic and occurrence of death data were collected. The cause of death was determined using the instrument of verbal autopsy.

RESULTS

The GMR for AP and Orissa was 636 (95% CI: 610-662) and 616 (95% CI: 588-643) per 100,000 person years (p-ys) respectively. The TMR for AP and Orissa was 76 (95% CI: 67-85) and 41 (95% CI: 34-48) per 100,000 p-ys respectively. The difference in TMR between the states was statistically significant (P<0.0001).

CONCLUSION

The GMRs are similar in AP and Orissa states. Tuberculosis accounted for 12% and 7% of deaths in AP and Orissa respectively. Focused strategies are needed to reduce mortality due to tuberculosis.

Biocompatibility of ferritin-based nanoparticles as targeted MRI contrast agents

Ferritin is a naturally occurring iron storage protein, proposed as a clinically relevant nanoparticle with applications as a diagnostic and therapeutic agent. Cationic ferritin is a targeted, injectable contrast agent to measure kidney microstructure with MRI. Here, the toxicity of horse spleen ferritin is assessed as a step to clinical translation. Adult male mice received cationic, native and high dose cationic ferritin (CF, NF, or HDCF) or saline and were monitored for 3weeks. Transient weight loss occurred in the ferritin groups with no difference in renal function parameters. Ferritin-injected mice demonstrated a lower serum iron 3weeks after administration. In ferritin-injected animals pre-treated with hydrocortisone, there were no structural or weight differences in the kidneys, liver, lung, heart, or spleen. This study demonstrates a lack of significant detrimental effects of horse-derived ferritin-based nanoparticles at MRI-detectable doses, allowing further exploration of these agents in basic research and clinical diagnostics.