Comparing the Clinical and Histological Diagnosis of Leprosy and Leprosy Reactions in the INFIR Cohort of Indian Patients with Multibacillary Leprosy

Leprosy affects skin and peripheral nerves. Although we have antibiotics to treat the mycobacterial infection, the accompanying inflammation is a major part of the disease process. This can worsen after starting antibacterial treatment with episodes of immune mediated inflammation, so called reactions. These are associated with worsening of nerve damage. However, diagnosing these reactions is not straightforward. They can be diagnosed clinically by examination or by microscopic examination of the skin biopsies. We studied a cohort of 303 newly diagnosed leprosy patients in India and compared the diagnosis rates by clinical examination and microscopy and found that the microscopic diagnosis has higher rates of diagnosis for both types of reaction. This suggests that clinicians and pathologists have different thresholds for diagnosing reactions. More work is needed to optimise both clinical and pathological diagnosis. In this cohort 43% of patients had Borderline Tuberculoid leprosy, an immunologically active type, and 20% of the biopsies showed only minimal inflammation, perhaps these patients had very early disease or self-healing. The public health implication of this work is that leprosy centres need to be supported by pathologists to help with the clinical management of difficult cases

Serological responses to prednisolone treatment in leprosy reactions: study of TNF-α, antibodies to phenolic glycolipid-1, lipoarabinomanan, ceramide and S100-B.

BACKGROUND: Corticosteroids have been extensively used in the treatment of immunological reactions and neuritis in leprosy. The present study evaluates the serological response to steroid treatment in leprosy reactions and neuritis. METHODS: Seven serological markers [TNF-α, antibodies to Phenolic glycolipid-1 (PGL-1 IgM and IgG), Lipoarabinomannan (LAM IgG1 and IgG3), C2-Ceramide and S100 B] were analyzed longitudinally in 72 leprosy patients before, during and after the reaction. At the onset of reaction these patients received a standard course of prednisolone. The levels of the above markers were measured by Enzyme linked immunosorbent assay (ELISA) and compared with the individuals own value in the month prior to the reaction and presented as percentage increase. RESULTS: One month before the reaction individuals showed a varying increase in the level of different markers such as TNF-α (53%) and antibodies to Ceramide (53%), followed by to PGL-1 (51%), S100B (50%) and LAM (26%). The increase was significantly associated with clinical finding of nerve pain, tenderness and new nerve function impairment. After one month prednisolone therapy, there was a fall in the levels [TNF-α (60%), C2-Ceramide (54%), S100B (67%), PGL-1(47%) and LAM (52%)] with each marker responding differently to steroid. CONCLUSION: Reactions in leprosy are inflammatory processes wherein a rise in set of serological markers can be detected a month before the clinical onset of reaction, some of which remain elevated during their action and steroid treatment induces a variable fall in the levels, and this forms the basis for a variable individual response to steroid therapy

Design of bio-nanosystems for oral delivery of functional compounds

Nanotechnology has been referred to as one of the most interesting topics in food technology due to the potentialities of its use by food industry. This calls for studying the behavior of nanosystems as carriers of biological and functional compounds aiming at their utilization for delivery, controlled release and protection of such compounds during food processing and oral ingestion. This review highlights the principles of design and production of bio-nanosystems for oral delivery and their behavior within the human gastrointestinal (GI) tract, while providing an insight into the application of reverse engineering approach to the design of those bio-nanosystems. Nanocapsules, nanohydrogels, lipid-based and multilayer nanosystems are discussed (in terms of their main ingredients, production techniques, predominant forces and properties) and some examples of possible food applications are given. Phenomena occurring in in vitro digestion models are presented, mainly using examples related to the utilization of lipid-based nanosystems and their physicochemical behavior throughout the GI tract. Furthermore, it is shown how a reverse engineering approach, through two main steps, can be used to design bio-nanosystems for food applications, and finally a last section is presented to discuss future trends and consumer perception on food nanotechnology.Miguel A. Cerqueira, Ana C. Pinheiro, Helder D. Silva, Philippe E. Ramos, Ana I. Bourbon, Oscar L. Ramos (SFRH/BPD/72753/2010, SFRH/BD/48120/2008, SFRH/BD/81288/2011, SFRH/BD/80800/2011, SFRH/BD/73178/2010 and SFRH/BPD/80766/2011, respectively) are the recipients of a fellowship from the Fundacao para a Ciencia e Tecnologia (FCT, POPH-QREN and FSE Portugal). Maria L. Flores-Lopez thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant number: 215499/310847). The support of EU Cost Actions FA0904 and FA1001 is gratefully acknowledged

Predicting neuropathy and reactions in leprosy at diagnosis and before incident events. Results from the INFIR cohort study

BackgroundLeprosy is a disease of skin and peripheral nerves. The process of nerve injury occurs gradually through the course of the disease as well as acutely in association with reactions. The INFIR (ILEP Nerve Function Impairment and Reactions) Cohort was established to identify clinically relevant neurological and immunological predictors for nerve injury and reactions.Methodology/Principal FindingsThe study, in two centres in India, recruited 188 new, previously untreated patients with multi-bacillary leprosy who had no recent nerve damage. These patients underwent a series of novel blood tests and nerve function testing including motor and sensory nerve conduction, warm and cold detection thresholds, vibrometry, dynamometry, monofilament sensory testing and voluntary muscle testing at diagnosis and at monthly follow up for the first year and every second month for the second year. During the 2 year follow up a total of 74 incident events were detected. Sub-clinical changes to nerve function at diagnosis and during follow-up predicted these new nerve events. Serological assays at baseline and immediately before an event were not predictive; however, change in TNF alpha before an event was a statistically significant predictor of that event.Conclusions/SignificanceThese findings increase our understanding of the processes of nerve damage in leprosy showing that nerve function impairment is more widespread than previously appreciated. Any nerve involvement, including sub-clinical changes, is predictive of further nerve function impairment. These new factors could be used to identify patients at high risk of developing impairment and disability

Reference values for nerve function assessments among a study population in northern India - III: sensory and motor nerve conduction

Objective: To identify reference values for normal sensory and motor nerve conduction in upper andlower limb peripheral nerves in a study population in India. The work was carried out in advanceof the INFIR Cohort Study, a prospective study of individuals with newly diagnosed multibacillaryMB leprosy, the objective being to identify early changes in nerve function predictive of new onsetimpairment and reactions. Methods: We assessed sensory nerve conduction in bilateral ulnar, median,radial cutaneous and sural nerves and motor nerve conduction in distal and proximal sites in bilateralulnar, median and peroneal nerves among 315 healthy subjects. After adjustment for skin temperatureand removal of outliers reference values were computed using regression analysis of log-transformeddata. The analysis and resulting reference values were stratifi ed by age and sex and based on theappropriate 5th or 95th percentiles. Results: Presented here are reference values for sensory nerveconduction velocity (SNCV), sensory nerve action potential (SNAP) amplitude and latency. Also formotor nerve conduction velocity (MNCV) and compound motor action potential (CMAP) amplitudeat proximal sites and for amplitude and latency at distal sites. In each case percentiles are given bysex within four 10 year age bands. For males aged 55 years old, the reference value for ulnar SNCVwas 43.6 m/sec and SNAP amplitude was 7.43 ?V. Ulnar MNCV at the proximal site in the elbowwas 50.8 m/sec and CMAP amplitude 7.25 mV and at distal sites in the wrist the amplitude was 7.14mV and latency 3.1 msec. In the leprosy-affected cohort, the most common and therefore potentiallythe earliest impairment, is found in sensory nerve conduction amplitude of the sural nerve

Reference values for nerve function assessments among a study population in northern India - I. Vibration perception thresholds

Objective: this paper presents normal reference values for vibration perception thresholds for a study population in northern India. The work was in preparation for the INFIR Cohort Study, a prospective study of people newly diagnosed with multibacillary leprosy which sought to identify early changes in nerve function predictive of new onset impairment and reactions. To establish the limits of normalfunction we collected data on subjects with no known neurological condition and computed the referencevalues defining the limits of normal function.Methods: data on vibration perception in 5 bilateral nerves was collected from 362 healthy subjects stratified by sex and by age and drawn from the same general population as the subsequent leprosy-affected cohort. Reference values were computed from log-transformed data after the exclusion of outliers. Results: normal reference values are presented in the form of 95th percentiles for vibration perception thresholds among normal subjects for 5 peripheral nerves within 8 age and sex groupings and by centre. The reference values are compared with those published for other populations. The incidence of impairment at diagnosis among the leprosy-affected cohort is described and illustrate

Reference values for nerve function assessments among a study population in northern India - II: thermal sensation thresholds

Objective: This paper presents normal reference values for thermal sensation for a study populationwith no known neurological condition in northern India. It was part of the INFIR Cohort Study, aprospective study of people newly diagnosed with multibacillary leprosy, the objective being to identifyearly changes in nerve function predictive of new onset impairment and reactions. Methods: Data onwarm and cold sensation in fi ve bilateral nerves was collected from 326 healthy subjects stratifi ed bysex and by age and drawn from the same general population as the subsequent leprosy-affected cohort.Reference values were computed from log-transformed data after the exclusion of outliers. Results:Normal reference values are presented in the form of 95th percentiles for warm and 5th percentilefor cold sensation within eight age and sex groups and by centre. The prevalence of impairment atdiagnosis among the leprosy-affected cohort is described and illustrated The high prevalence of lostwarm sensation in the leprosy-affected cohort suggests that this is an important early indicator fornerve involvement in leprosy

The INFIR Cohort Study: assessment of sensory and motor neuropathy in leprosy at baseline.

AIM: To compare different method(s) to detect peripheral neuropathy in leprosy and to study the validity of the monofilament test (MF) and the voluntary muscle test (VMT) as standard tests of nerve function. DESIGN: A multi-centre cohort study of 303 multibacillary (MB) leprosy patients. METHODS: Newly registered MB patients requiring a full course of MDT were recruited in two leprosy outpatient clinics in North India. Controls were people without leprosy or neurological conditions, attending the dermatological outpatient departments of the same clinics. Nerve function was evaluated electrophysiologically using standard parameters for sensory and motor nerve conduction (NC) testing, warm and cold detection thresholds (W/CDT), vibration perception thresholds, dynamometry, MF and VMT. The latter two defined the outcomes of sensory and motor impairment. RESULTS: 115 patients had nerve damage or a reaction of recent onset at diagnosis. Sensory and motor amplitudes and WDTs were the most frequently abnormal. Among the nerves tested, the sural and posterior tibial were the most frequently impaired. In the ulnar nerve, sensory latencies were abnormal in 25% of subjects; amplitudes in 40%. Ulnar above-elbow motor conduction velocities were abnormal in 39% and amplitudes 32%. WDTs were much more frequently affected than CDTs in all nerves tested. The thresholds of all test parameters differed significantly between controls and patients, while only some differed between patients with and without reaction. Good concordance was observed between MF results and sensory latencies and velocities (direct concordance 80% for the ulnar). However, a proportion of nerves with abnormal MF results tested normal on one or more of the other tests or vice versa. Concordance between VMT and motor conduction velocities was good for the ulnar nerve, but for the median and peroneal nerves, the proportion impaired by VMT out of those with abnormal motor conduction was very low. CONCLUSIONS: Concordance between monofilaments and other sensory function test results was good, supporting the validity of the monofilaments as standard screening test of sensory function. Concordance between VMT results and motor nerve conduction was good for the ulnar nerve, but very few median and peroneal nerves with abnormal conduction had an abnormal VMT. A more sensitive manual motor test may be needed for these nerves. Of the nerve assessment tests conducted, NC amplitudes and warm sensation were the most frequently affected. Therefore, nerve conduction studies and WDT measurements appear to be most promising tests for early detection of leprous neuropathy. The pattern of concordance between tactile and thermal sensory impairment failed to support the hypothesis that small fibre neuropathy always precedes large fibre damage. Warm sensation was more frequently affected than cold sensation. This could indicate that unmyelinated C fibres are more frequently affected than small myelinated Asigma fibres

Voluntary muscle testing and dynamometry in diagnosis of motor impairment in leprosy: a comparative study within the INFIR cohort study

Aim: to evaluate hand muscle weakness detected through dynamometry as an indicator for change in motor nerve function detected by Voluntary Muscle Testing (VMT) of ulnar and median nerves.Design: the research was carried out as part of the INFIR Cohort Study among 303 subjects newly diagnosed with MB leprosy in two centres in UP state, northern India.Methods: To assess grip strength, key pinch and pulp-to-pulp pinch we adapted the cuffs of adult and neonatal sphygmomanometers. The testing was carried out atdiagnosis and at each visit during a 2-year follow-up.Results: 303 subjects with newly diagnosed MB leprosy were included in the study. We found statistically significant differences in grip strength, key pinch and pulp-to-pulp pinch between groups defined by ulnar VMT grades at time of diagnosis. There was also a statistically significant difference in hand grip between groups defined by median VMT at diagnosis. In each case, strength tended to reduce with increasing motor involvement. We explored reduction in grip strength, key pinch or pulp-to-pulp pinch as indicators of change in ulnar VMT during follow-up. A 25%reduction over two visits was the most effective indicator. Changes were also associated with marginal changes in motor and sensory nerve function, most commonly associated with Type I reactions. Conclusion: dynamometry is recommended as an additional method that may be used to monitor changes in nerve function in leprosy, particularly in subjects with early motor impairment of the ulnar nerve