Role of Bilastine in Allergic Rhinitis: A Narrative Review.

Allergic rhinitis (AR) is considered a trivial disease and is often self-treated with over-the-counter drugs and home remedies. However, AR is a contributing risk factor for asthma associated with complications, including chronic cough, eosinophilic esophagitis, and otitis media with effusion. In AR, inflammation is primarily mediated by histamines. Guidelines advise using second-generation oral H1 antihistamines as the primary treatment for AR. Second-generation H1 antihistamines strongly prefer the H1 receptor, limiting their ability to enter the central nervous system. Thus, they have minimal adverse effects. Among these H1 antihistamines, bilastine is highly specific for H1 receptors with a slight affinity for other receptors. It has a rapid and prolonged action, which reduces the need for frequent dosing and has better compliance. In the long term, bilastine is well-tolerated with minimal adverse effects. It is not associated with drug interactions, so dosage adjustment is unnecessary. Bilastine does not penetrate the brain and is nonsedating at 80 mg once daily. The low possibility of drug-drug interactions and pharmacokinetics of bilastine makes it suitable for elderly patients, even with compromised hepatic and renal function, without dose adjustment. This review comprehensively discusses the guidelines and the role of bilastine in treating AR. How to cite this article: Tiwaskar M, Vora A, Tewary K, et al. Role of Bilastine in Allergic Rhinitis: A Narrative Review. J Assoc Physicians India 2023;71(11):58-61.

SARS-CoV-2, Uncontrolled Diabetes and Corticosteroids-An Unholy Trinity in Invasive Fungal Infections of the Maxillofacial Region? A Retrospective, Multi-centric Analysis.

OBJECTIVES: Collate and analyse data of maxillofacial/rhino-cerebro-orbital fungal infections reported during the era of the Covid-19 pandemic, with the aim of investigating the common contributing factors leading to such infections and of highlighting the significance of this surge seen in patients infected with SARS-CoV-2. METHOD: This retrospective observational multi-centric study analysed patient data collected from clinicians belonging to different specialties in Bangalore, India. The data included the presentation and management of patients presenting with aggressive maxillofacial and rhino-cerebro-orbital fungal infections and explored the relationship between SARS-CoV-2, corticosteroid administration and uncontrolled diabetes mellitus. RESULTS: All 18 patients were Covid positive. Sixteen of the 18 patients received steroids for Covid treatment and 16 patients were diabetic (of whom 15 patients who were diabetics received steroids for Covid-19 treatment). Loss of vision was noted in 12 of the 18 patients and 7 of them underwent orbital exenteration. The fungi noted was mucormycosis in 16 patients, aspergillosis in 1 patient and a mixed fungal infection in 1 patient. Eleven of the patients survived, 6 died and 1 was lost to follow-up. There was a significantly higher incidence of diabetes (p = 0.03) amongst these cohort of patients who were Covid-19 positive with mucormycosis. A significantly higher number (p = 0.0013) of patients were administered steroids at some point during the treatment. CONCLUSION: Despite the limited sample size, it is evident that there is a significant increase in the incidence of angioinvasive maxillofacial fungal infections in diabetic patients treated for SARS-CoV-2 with a strong association with corticosteroid administration.

Objective criteria for diagnosing high altitude pulmonary edema in acclimatized patients at altitudes between 2700 m and 3500 m.

BACKGROUND: The criteria used for diagnosing high altitude illnesses are largely based on Western literature. This study was undertaken to define objective, simple and reliable diagnostic criteria for high altitude pulmonary edema (HAPE) in Indian soldiers at altitudes between 2700 m and 3500 m. METHODS: Clinical data of 235 cases of HAPE that occurred between 2700 m and 3500 m were analysed. Receiver operator characteristic (ROC) curve analysis was used to select simple clinical parameters suitable for the diagnosis of HAPE at peripheral medical facilities. Cut-off values and their reliability for the diagnosis of HAPE were defined. RESULTS: HAPE occurred 2.8 ± 2.2 days after arrival at altitudes between 2700 m and 3500 m. Breathlessness, cough, chest discomfort and headache were the commonest symptoms. Low pulse oximetry (SPO2) values than normal for this altitude were seen in 89% of patients. ROC analysis of clinical parameters identified a heart rate more than 95 beats per minute (bpm), respiratory rate more than 21 per minute and SPO2 less than 86% while breathing ambient air at this altitude as diagnostic of HAPE. The sensitivity and specificity of these cut-offs was 0.66, 0.83 and 0.82 and 0.94, 0.95 and 0.93 respectively. CONCLUSION: A heart rate of more than 95 bpm, respiratory rate more than 21 per minute and SPO2 less than 86% breathing room air in individuals complaining of breathlessness, cough, chest discomfort or headache within the first 5 days of arrival at altitudes between 2700 m and 3500 m is highly suggestive of HAPE.

Very low frequency oscillations in the power spectra of heart rate variability during dry supine immersion and exposure to non-hypoxic hypobaria.

The origin of very low frequency (VLF) oscillations in the power spectra of heart rate variability (HRV) is controversial with possible mechanisms involving thermoregulation and/or renin-angiotensin-aldosterone system. Recently, a major contribution from vagal influences has been suggested. The present study investigated the behaviour of VLF (0.004-0.040 Hz) components of HRV power spectra in a group of healthy male volunteers during their exposure to (1) dry, supine, immersion in thermo-neutral water for 6 h (n = 7) and (2) non-hypoxic hypobaria (breathing 40-60% oxygen at 15,000' simulated in a decompression chamber) for 5 h (n = 15). The two manoeuvres are established to increase vagal outflow. During both the manoeuvres, all the frequency domain indices of HRV exhibited a significant increase. Increase in HRV was much more than that in the R-R interval. At 6 h of immersion, the R-R interval increased by ∼ 15% but the total power increased ∼ fourfold. Similarly, at 5 h of exposure to hypobaria, total power increased ∼ twofold with a very modest increase in an R-R of ∼ 9%. Increase in spectral power was appreciable even after normalization with mean R-R(2). Increase in VLF during immersion was more than reported during enalaprilat blockade of angiotensin convertase enzyme. Plasma renin activity did not vary during hypobaria. There was a significant increase in pNN50, an established marker of cardiac vagal activity. Centre frequencies of the spectra and slope (ß) of the relation between log(PSD) and log(frequency) did not change. Results were supportive of the notion that the parasympathetic system is pre-potent to influence slower (than respiratory) frequency components in HRV spectrum. Additionally, such an effect was without a change in the time constant of effector responses or pacemaker frequencies of VLF and LF periodicities and HRV was not a simple linear surrogate for cardiac vagal effects. An invariance of spectral exponent (ß) ruled out contamination of VLF and LF spectra from fractal power as an alternate explanation.

Evaluation of efficacy and tolerability of Losartan and Ramipril combination in the management of hypertensive patients with associated diabetes mellitus in India (LORD Trial).

AIM: The study was conducted to evaluate efficacy and tolerability of fixed dose combination (FDC) of Losartan and Ramipril in the management of mild to moderate hypertensive Native Asian Indian patients with associated diabetes mellitus. The secondary objective was to evaluate the efficacy of the combination in reducing microalbuminuria. MATERIAL AND METHODS: The study was an open, non-comparative, multicentric clinical trial conducted in seven Indian centres in 315 eligible patients. All the patients were treated with Losartan 50 mg + Ramipril 2.5 mg or Losartan 50 mg + Ramipril 5 mg once a day in 12 weeks and consisted of a total of eight visits. RESULTS: The mean age of patients was 52.93 years (range 45 - 60 years). Of the total patients, 62.86% were males and 37.14% were females. The mean prestudy systolic blood pressure was 160.56 +/- 14.44 which was significantly reduced to 126.85 +/- 9.78 at the end of 12 weeks (P < 0.001). Similarly the mean diastolic blood pressure was 98.91 +/- 8.33 at baseline (stage I) which was significantly reduced to 79.82 +/- 5.42 at the end of 12 weeks (P < 0.001). A mean fall of 33.72 mmHg in systolic blood pressure and the mean fall of 19.10 mmHg was observed in systolic and diastolic blood pressure respectively at the end of the treatment which was statistically highly significant (P < 0.001). The JNC-VII goal of blood pressure < 130/80 was achieved in 79.05% patients after the treatment which losartan and ramipril combination only. Microalbuminuria (urinary albumin excretion > 30 but < 300 mg/day) was seen in 83/250 (33.2%) patients and 135 (54%) patients had clinical proteinuria (albuminuria) at baseline. At the end of the therapy 20.8% patients achieved normoalbuminuria. Good to excellent efficacy response was reported in 98.09% patients and 98.41% patients reported good to excellent tolerability to the treatment. CONCLUSION: The fixed dose combination of Losartan and Ramipril showed good to excellent efficacy response in 98.10% patients and achieved a target blood pressure of 130/80 mmHg in 79.05% patients in 12 weeks. The combination reduced the urinary albumin excretion in majority of the patients with microalbuminuria and proteinuria (the major marker of nephropathy).

Microorganisms as an alternative source of protein.

Demand for human food and animal feed proteins from nonconventional sources has increased, particularly in developing countries. Microbial protein is one such source. It is desirable because it is amenable to controlled intensive cultivation and is less dependent on variations in climate, weather, and soil. Microbial proteins must be evaluated for nutritive value, safety, and economic considerations before mass production is undertaken.

Rifamycins: strain improvement program.

Rifamycins are primarily produced by Gram-positive bacterium Amycolatopsis mediterranei, which belongs to the order Actinomycetales. These antibiotics, apart from their application against pathogens of tuberculosis and leprosy, have also been found to be effective against several other pathogens including Mycobacterium avium and Pneumococcus. Because of the importance of rifamycin, the producer strain A. mediterranei has been genetically manipulated since 1957 in order to develop a strain that can either produce larger amounts of rifamycin or derivatives of rifamycin. In this article, the importance of the producer strain, traditional methods (mutations and recombination) of strain improvement, their limitations, and the development of a cloning vector and transformation methods that have made recombinant DNA techniques accessible for genetic manipulations of A mediterranei are discussed.

Reduction in the dosage schedule of BPL-inactivated neural tissue vaccine for rabies prophylaxis in man.

There exist two different immunization schedules for neural tissue rabies vaccine (NTV) for human use in India, the amount of vaccine given by the schedule recommended by Central Research Institute (CRI), Kasauli, being higher than that recommended by Pasteur Institute of India (PII), Coonoor. A study was therefore undertaken to assess the feasibility of reducing the CRI dosage schedule for rabies prophylaxis. The antirabies antibody response in laboratory animals and human subjects following 7, 10 and 14 daily doses of NTV with or without administering rabies immune globulin (RIG) was much higher than the minimum protective level of 0.5 IU/ml of serum. Based on these results, the CRI schedule could be reduced from 14 x 5 ml of NTV to 10 x 5 ml in class II and class III rabies exposure cases.

Oral infectivity of street and fixed rabies virus strains in laboratory animals.

Oral transmission of rabies could be produced in laboratory animals like mice, guinea pigs and hamsters using challenge virus strain (CVS) and 2 strains of street virus. Study of virus pathway following ingestion suggested predominant neural spread to brain and centrifugal spread to non neural organs like heart and kidneys. However it was found that virus dose required for oral infection was relatively very high. The role of such a transmission in nature needs to be further evaluated, keeping in view the high dose of virus required for oral infectivity and the frequency of consumption of brain by carnivorous animals.

Lytic effect of Vibrio cholerae elastase on gram-positive and -negative bacteria.

Elastase of Vibrio cholerae caused the lysis of freshly grown cells of Gram-negative (Pseudomonas aeruginosa, Proteus vulgaris, Salmonella paratyphi A and Klebsiella pneumoniae) bacteria. Gram-positive (Staphylococcus aureus and S. epidermidis) organisms were resistant to this enzyme. Heat killed and lyophilized Gram-positive and -negative bacteria (except S. aureus and S. epidermidis) showed higher sensitivity to elastase. Both Gram-negative and -positive bacteria were lyzed maximally by elastase at pH 8.0. At this pH, lytic activity of elastase was maximum in Tris-HCl and glycine-NaOH buffers followed by Tris-maleate and cacodylate buffers.

Evaluation of the new rapid rabies immunodiagnosis technique.

The rapid rabies enzyme immuno-diagnosis (RREID) kit was evaluated for its sensitivity and specificity in comparison to fluorescent antibody technique (FAT) and biological test (BT) for the diagnosis of rabies. While 93 per cent correlation was observed in case of fresh brain samples, 71 per cent correlation was noted with glycerol preserved samples, where RREID was more sensitive than FAT. RREID test can be employed for rapid diagnosis of rabies, when facilities for FAT are not available. However, to test, at one time, small number of specimens, the RREID kit needs to be modified.

Production and partial characterization of elastase of Vibrio cholerae Inaba.

Conditions are described for the production of extracellular elastase by Vibrio cholerae Inaba 2/57. The yield of the enzyme was maximum in shake cultures grown in alkaline peptone water at 37 degrees C and was stable in culture supernatants. The enzyme, partially purified by ammonium sulphate precipitation and Sephadex G-100 gel filtration showed a molecular weight of 30,000 and an activity between pH 5.0-8.0 with an optimum of 8.0 in Tris-maleate buffer. The elastinolytic activity was maximal in glycine-NaOH buffer and minimal in phosphate buffer. The enzyme activity was adversely affected by temperature greater than or equal to 40 degrees C.

Post exposure studies with human diploid cell rabies vaccine and purified chick embryo cell vaccine: comparative serological responses in man.

Rabies-neutralising antibody responses to human diploid cell strain rabies vaccine (HDCSV) and purified chick embryo cell vaccine (PCECV) were studied in 125 patients previously exposed to rabid animals having received 3, 5 and 6 doses on days 0, 3, 7, 14, 30 and 90. Antibody response was significantly higher (P less than 0.05) with HDCSV than PCECV in all subjects irrespective of their sex and age group. Three doses on day 0, 3, 7 given for post-exposure rabies prophylaxis to class I patients with a negligible risk elicited antibody titres significantly higher than the minimum protective level required (0.5 I.U./ml); the mean response was greater than 15 I.U./ml in the case of PCECV and greater than 32 I.U./ml in the case of HDCSV. The use of PCECV is cost-effective and suggested for use in developing countries.