Studies on community knowledge and behavior following a dengue epidemic in Chennai city, Tamil Nadu, India

In 2001, a major dengue outbreak was recorded in Chennai city, with 737 cases (90%) out of a total of 861 cases recorded from Tamil Nadu state. A KAP survey was carried out to assess the community knowledge, attitude and practice on dengue fever (DF), following the major dengue outbreak in 2001. A pre- tested, structured questionnaire was used for data collection. The multistage cluster sampling method was employed and 640 households (HHs) were surveyed. Among the total HHs surveyed, 34.5% of HHs were aware of dengue and only 3.3% of HHs knew that virus is the causative agent for DF. Majority of the HHs (86.5%) practiced water storage and only 3% of them stored water more than 5 days. No control measures were followed to avoid mosquito breeding in the water holding containers by majority of HHs (65%). Sixty percent of HHs did not know the biting behaviour of dengue vector mosquitoes. The survey results indicate that the community knowledge was very poor on dengue, its transmission, vector breeding sources, biting behavior and preventive measures. The lack of basic knowledge of the community on dengue epidemiology and vector bionomics would be also a major cause of increasing trend of dengue in this highly populated urban environment. There is an inevitable need to organize health education programmes about dengue disease to increase community knowledge and also to sensitize the community to participate in integrated vector control programme to resolve the dengue problem.

Molecular identification of mosquito vectors using genomic DNA isolated from eggshells, larval and pupal exuvium

Correct and precise identification of mosquito vectors is important in many respects including development of vector control strategies. Conventional identification methods have limitations for sibling and closely related species of mosquitoes, stage and quality of the specimen used and this could be overcome by DNA-based identification methods using molecular markers such as nuclear ribosomal internal transcribed spacer (ITS) which do not demand intact or undamaged specimen. Genomic DNA is usually isolated from whole mosquito, legs, wings etc. Alternate sources for genomic DNA isolation such as eggshells, larval and pupal exuviae were explored in this study by amplifying the ITS markers. Standardization of genomic DNA extraction and ITS amplification were carried out with laboratory specimens. The same was applied to specimens collected from the field. The results show that PCR amenable genomic DNA could be isolated from fresh exuviae collected in the laboratory and not from older and/or field specimens. But exuviae of larvae and/or pupae collected in the field reared to adulthood in the laboratory yielded PCR amenable genomic DNA. The results also revealed that the ITS2 marker could very well differentiate Aedes aegypti and Aedes albopictus by producing amplicons of ~330 bp and ~520 bp, respectively. The genomic DNA from these alternate sources also supported the species-specific PCR to distinguish the Culex vishnui subgroup mosquitoes.

A study on chikungunya outbreak during 2007 in Kerala, south India

BACKGROUND & OBJECTIVE

The first chikungunya outbreak occurred in Kerala during 2006 affecting 14 districts, followed by another during May 2007 affecting almost whole of the State. Four of the worst affected districts viz, Pathanamthitta, Idukki, Kottayam and Thrissur were surveyed during 2007 to understand the magnitude of the problem of chikungunya fever, particularly clinical signs and symptoms.

METHODS

A total of 1265 persons from 310 houses were surveyed door-to-door in 20 different localities representing four affected districts. The history and examination findings from 354 clinically diagnosed chikungunya cases were recorded. The symptoms recorded were fever, headache, myalgia, arthralgia, itch/rash, oedema, eye congestion, eye pain, oral ulcers, distaste, nausea, vomiting and haemorrhage.

RESULTS

The major symptoms were fever (100%), headache (97.5%), arthralgia (99.4%) and myalgia (99.4%). A significant difference was observed in oedema, distaste, nausea and headache among different age groups and these symptoms were reported to be lower (12.2-89.8%) in younger age group than in older age group (90.4-100%). No genderwise difference was observed for any of the symptoms. In clinically diagnosed chikungunya cases higher age group (>35 years) found with higher rate of severity with symptoms of oedema, distaste, nausea and headache when compared with lower age group (1-35 yr).

INTERPRETATION & CONCLUSION

Chikungunya invaded Kerala State for the first time in 2006 and continues to be a major vector borne disease in the State. The clinical symptoms in affected cases highlighted high fever, sever myalgia and prolonged arthralgia, with occasional history of skin itch/rash (petechiae).

Natural vertical transmission of dengue viruses by Aedes aegypti in Chennai, Tamil Nadu, India

BACKGROUND & OBJECTIVE

Dengue viruses are spread and maintained in an Aedes aegypti-human- Ae. aegypti cycle in urban areas of the tropics. Dengue viruses are also maintained in nature by vertical transmission by Ae. aegypti. A study was undertaken in Chennai, a known endemic city in south India, to comprehend the natural vertical transmission dynamics in Ae. aegypti and to assess its epidemiological importance.

METHODS

Ae. aegypti males collected in resting and landing collections were tested for dengue virus infection by antigen-capture enzyme-linked immunosorbent assay (ELISA) and further examined by insect bioassay, Toxorhynchites splendens inoculation-indirect immunofluorescence technique (Toxo-IFA) using serotype-specific monoclonal antibodies (Mabs), if found positive by ELISA.

RESULTS

Of the 509 pools of Ae. aegypti males (n=5408) screened, 15 pools, collected in April, June- July, November-December in 2003 and March, May in 2004, were found positive for dengue virus infection and the minimum infection rate (MIR) among adult males was high in June 2003 (28.0/ 1000). Three positive pools could be serotyped as dengue-2 (2 pools) and dengue-3 (1 pool).

INTERPRETATION & CONCLUSION

Dengue virus isolations from wild caught males of Ae. aegypti indicate the occurrence of transovarial transmission. Vertical transmission was mainly observed in summer months when dengue infections in humans were low suggesting that dengue viruses adopt a novel strategy of surviving adverse climatic conditions.

Desiccated vector mosquitoes used for the surveillance of Japanese encephalitis virus activity in endemic southern India

To monitor Japanese encephalitis virus (JEV) activity in endemic areas of Tamil Nadu, southern India, desiccated vector mosquitoes were screened for JEV antigen using ELISA, from 1996. A total of 133 233 specimens from eight index villages comprising 2816 pools (mainly Culex vishnui subgroup) were tested. Of these, 59 pools (2.1%) were positive for JEV antigen. Control measures were undertaken in positive villages accordingly. The average annual minimum infection rate was 0.8 at the beginning of the study and remained lower for nearly 8 years. A declining trend in JE cases was recorded.

Comparison of CD4 and CD8 lymphocyte counts in HIV-negative pulmonary TB patients with those in normal blood donors and the effect of antitubercular treatment: hospital-based flow cytometric study

BACKGROUND

This study was designed to flow cytometrically determine baseline and sequential values of CD4 and CD8 lymphocyte subsets in patients without the human immunodeficiency virus and with pulmonary tuberculosis (TB) and to correlate these values with those obtained from normal male blood donors and with the radiologic extent of disease and response to therapy.

METHODS

We studied 39 male patients without the human immunodeficiency virus and with sputum positive for pulmonary TB who had been admitted to Military Hospital (Cardiothoracic Center) in Pune, India. Clinical, laboratory, and radiologic evaluations of these patients were done. Hematologic parameters were assessed by an automated hematology cell counter (AcT*Diff, Coulter), and T-cell subsets (CD4 and CD8) were determined flow cytometrically (EPICS-XL, Coulter).

RESULTS

CD4 counts and percentages of CD4 were significantly lower, but CD8 values were normal, in patients with pulmonary TB when compared with values obtained in normal blood donors. The CD4/CD8 ratio was significantly lower in patients with TB. The CD4 counts normalized with antitubercular treatment. The radiologic extent of disease did not correlate well with the immune parameters studied.

CONCLUSIONS

TB is a reversible cause of CD4 lymphocytopenia and is associated with normal numbers of CD8 cells. The radiologic extent of disease does not seem to determine the immune response.

Verrallina (Neomacleaya) assamensis, a new species from Assam, India

The adult female, adult male, pupa, and larva of Verrallina (Neomacleaya) assamensis, a new mosquito species, are described from the Dibrugarh District of Assam State, India.

Dengue vector prevalence and virus infection in a rural area in south India

We conducted a 2-year (1997-1999) longitudinal, entomological and virological study in three dengue endemic villages in Vellore district, Tamil Nadu, to understand the dynamics of dengue transmission. Aedes aegypti (Linn.), Ae. albopictus (Skuse) and Ae. vittatus (Bigot) were the prevalent vector species. Aedes aegypti was breeding throughout the year with a Breteau index ranging from 9.05 to 45.49. Aedes albopictus and Ae. vittatus were prevalent mainly in the rainy season. Small water holding containers (cemented tanks/cisterns) were the perennial breeding source of Ae. aegypti, and its abundance was significantly higher in semi-urbanized central areas than the peripheral areas of the villages. From 271 pools (4016 specimens) of adult females, eight dengue virus (DENV) isolates were obtained of which seven were from Ae. aegypti and one from Ae. albopictus. This is the first report of DENV isolation from Ae. albopictus in rural India. Infection rates in the two species were comparable. However, due to higher and perennial prevalence, Ae. aegypti is considered as primary vector with Ae. albopictus playing a secondary role. Despite circulation of all four serotypes (DENV 1-4) detected mainly during the transmission season, the high anthropophilic index of the vectors and their abundance, no human dengue case was reported, suggesting silent dengue transmission.

Transmission intensity index to monitor filariasis infection pressure in vectors for the evaluation of filariasis elimination programmes

We conducted longitudinal studies on filariasis control in Villupuram district of Tamil Nadu, south India, between 1995 and 2000. Overall, 23 entomological (yearly) data sets were available from seven villages, on indoor resting collections [per man hour (PMH) density and transmission intensity index (TII)] and landing collections on human volunteers [PMH and annual transmission potential (ATP)]. All four indices decreased or increased hand-in-hand with interventions or withdrawal of inputs and remained at high levels without interventions under varied circumstances of experimental design. The correlation coefficients between parameters [PMH: resting vs. landing (r = 0.77); and TII vs. ATP (r = 0.81)] were highly significant (P < 0.001). The former indices from resting collections stand a chance of replacing the latter from landing collections in the evaluation of global filariasis elimination efforts. The TII would appear to serve the purpose of a parameter that can measure infection pressure per unit time in the immediate household surroundings of human beings and can reflect the success or otherwise of control/elimination efforts along with human infection parameters. Moreover, it will not pose any additional risk of new infection(s) and avoids infringement of human rights concerns by the experimental procedures of investigators, unlike ATP that poses such a risk to volunteers.

Dengue disease spectrum among infants in the 2001 dengue epidemic in Chennai, Tamil Nadu, India

An investigation in a referral pediatric hospital has indicated that during a recent dengue outbreak in Chennai, Tamil Nadu, India, dengue in infancy constituted 20% of total dengue virus infections with low mortality rates in this hospital. In developing countries, strengthening of dengue management capabilities at hospitals can prevent dengue-related deaths in infants.

Longitudinal studies in South Indian villages on Japanese encephalitis virus infection in mosquitoes and seroconversion in goats

Japanese encephalitis (JE) is endemic in Cuddalore district, Tamil Nadu, where Culex tritaeniorhynchus Giles was the major vector. We screened 45 100 adult female Cx. tritaeniorhynchus (902 pools) by enzyme-linked immunosorbent assay and isolated and confirmed JE virus (JEV) by using an insect bioassay system. We had 69 isolates of which 62 (90%) were identified as JEV. The average vector abundance per man hour for Cx. tritaeniorhynchus was 324.5 per month for the period June 1998-May 2000. The average minimum infection rate (MIR) per month in Cx. tritaeniorhynchus was 1.4 (range 0.0-5.6). Every year, a new batch of goats, 20 in the first year and 31 in the second year, born during the non-JE transmission period (January-June), aged <6 months and negative for haemagglutination inhibition (HI) antibodies were procured and placed in the villages as sentinels. Fortnightly, blood specimens were collected from these goats and tested for JE antibodies by HI test. Seroconversions (SCs) were recorded in 14 goats (70%) in the first year and 23 goats (74%) in the second year. JE HI antibody titres in goats were low (1:10-1:80) and these levels declined to undetectable levels in about 4 weeks following SCs. The time sequence of events indicated that four of five peaks of MIR in mosquitoes were followed 1-3 months later by peaks in the proportion of seroconverted goats. We suggest the screening of goats and cattle as a more feasible tool to stratify areas according to JE infection risk to the human population through the regular health system rather than screening mosquitoes using monoclonal antibodies, which is possible only in specialized laboratories.

A COMPARATIVE STUDY OF CHEST RADIOGRAPHIC FEATURES BETWEEN HIV SEROPOSITIVE AND HIV SERONEGATIVE PATIENTS OF PULMONARY TUBERCULOSIS

Chest radiographic appearance of pulmonary tuberculosis (TB) in Human Immunodeficiency Virus (HIV) positive patients was reviewed. A study group of 50 HIV +ve cases and a control group of 100 HIV -ve cases were analysed. The chest radiographs of HIV seropositive group showed significantly higher incidence of thoracic lymphadenopathy (36% vs 8%, P<.001), pleural effusion (28% vs 10%, P<.01) and miliary pattern (12% vs 2%, P<.05) as compared to the seronegative group. Cavitation was less common in the seropositive group (8% vs 35%, P<.001) than the seronegative group. Upper zone involvement was significantly less common in the study group (38% vs 77%, P<.001) as compared to the control group.

Resurgence in filarial transmission after withdrawal of mass drug administration and the relationship between antigenaemia and microfilaraemia--a longitudinal study

Seven village units endemic for filariasis were assigned randomly into three arms with different intervention strategies in the years 1995 and 1996. Villages in Group A received two annual mass drug administrations (MDAs) of diethylcarbamazine (DEC) plus ivermectin (IVR). Group B received the same MDAs in combination with vector control; in Group C only placebo was administered. Post-treatment evaluation in 1997 revealed marked reductions in microfilaraemia prevalences (MFP) and geometric mean intensities (GMI). Subsequently, vector control in Group B was continued by the community. Groups A and B received no MDAs between 1997 and 1999 and were re-evaluated in 1999. During this evaluation, antigenaemia prevalence (AGP) was estimated along with MFP, using immunochromatographic test (ICT) kits. The gains of the MDAs were sustained in Group B, while resurgences occurred in Group A, where annual transmission potential (ATP) rose from 21 to 631.6 and MFP doubled. Group C continued to have high ATPs (1057-1617), while Group B had very low ATPs (0-63). After Mulla's corrections, the reductions in MFP were 62.7 and 83.5% and for GMI 72.1 and 91.4% in Group A and B, respectively, compared with Group C. Vector control preserved the gains of MDAs and accounted for 55.8% and 67.1% reductions in MFP and GMI in Group B compared with Group A. The reductions in AGP were 29.4% in Group A and 39.2% in Group B against Group C. The differences between MFP and AGP were nearly uniform across all villages and there was a significant correlation (r=0.98) between the two variables. A similar significant relationship was observed between MFP and AGP values across age groups (r=0.95). Prediction of AGP values from MFP values was proposed with regression equations. We conclude that vector control would be useful as an adjuvant to chemotherapy to prevent resurgences.

Neutralizing and complement-fixing monoclonal antibodies as an aid to the diagnosis of equine herpesvirus-1 infection

One complement-fixing (C-MAb) and three complement-dependent neutralizing monoclonal antibodies (N-MAbs) were raised against Hisar-90-7 equine herpesvirus-1 (EHV-1) strain. The target antigen of the C-MAb (2A5) and two of the N-MAbs (1H6, 9C4) was identified as a 140 kDa polypeptide in Western blotting. The target antigen of N-MAb (9C6) could not be identified. Purified polypeptides of five EHV-1 strains isolated from different regions and at different times gave intense bands at 140 kDa when reacted with N-MAb (1H6) in Western blots. In sandwich ELISA, all four MAbs captured the viral antigen from clinical materials, giving a reliable and rapid diagnosis of EHV-1 infection in equines.

Annual single-dose diethylcarbamazine plus ivermectin for control of bancroftian filariasis: comparative efficacy with and without vector control

Two intervention strategies for the control of bancroftian filariasis were compared in rural villages of southern India: annual mass treatment with single-dose diethylcarbamazine plus ivermectin, either on its own or combined with vector control. Vector control, based on the use of polystyrene beads and larvivorous fishes in the major breeding sites of Culex quinquefasciatus, brought about a drastic and sustained reduction in vector density and man-biting rates. After the first round of treatment, chemotherapy alone brought about a 60% drop in the annual transmission potential (ATP) whereas the integrated strategy reduced ATP by 96% (P < 0.05). After two annual rounds of treatment, the reduction in ATP was similar for both strategies (91%-96%), with the prevalences of microfilaraemia reduced by 88%-92%. However, when drug pressure was removed in the third and final year of the study, transmission was resumed in the absence of vector control whereas no infective female mosquitoes were detected in the villages with vector control. Vector control, though obviously not cost-effective in the short term, could play an important role in an integrated programme, by preventing re-establishment of transmission after chemotherapy is completed.

Lung function in mitral stenosis

OBJECTIVES

The aim of this study was to look to for a relationship between pulmonary artery pressure (PAP), left atrial pressure (LAP), mitral valve area (MVA) and transmitral gradient (Gr) on the one hand and the spirometric data on the other, in cases of mitral stenosis.

METHODS

The spirometry values measured were forced vital capacity (FVC), forced expiratory volume in one second and as percent of FVC (FEV1, FEV1/FVC%), forced expiratory flow between 25% to 75% of FVC (FEF 25-75%), at 50% of FVC (FEF 50%) 75% of FVC (FEF 75%) and peak expiratory flow rate (PEFR). The PAP, LAP, MVA and Gr were measured at echocardiography and cardiac catheterisation.

RESULTS

Analysis of results was done of 60 patients in four groups divided on basis of mean PAP: Group 1 with least and group 4 with highest mean PAP. FVC values were reduced in direct proportion to PAP, LAP, MVA and Gr in three out of four groups. FEV1% as a percent of predicted value showed uniform reduction in all the groups, PEFR was moderately affected in group 1 and most severely in group 4. Values of FEV1/FVC% were within normal range in all the groups. FEF 25-75%, and FEF 50% showed serial reduction in values in keeping with the elevation of the PAP. FEF 75% was also moderately affected in group 1 and most severely in group 4.

CONCLUSION

We found that a moderate restrictive defect and a small airway defect which is found in cases of mitral stenosis, directly correlates to the PAP, LAP, MVA and Gr. There was no significant involvement of the larger airways.

PREVALENCE OF DRUG RESISTANT TUBERCULOSIS IN ARMED FORCES-STUDY FROM A TERTIARY REFERRAL CHEST DISEASES HOSPITAL AT PUNE

This study was conducted to find out the prevalence and pattern of primary and acquired resistance to antimycobacterial drugs among patients of pulmonary tuberculosis, in Armed Forces. Out of 2562 clinically diagnosed patients of tuberculosis, in a span of three years, 1146 were bacteriologically positive. The study included only 1120 smear and culture positive cases, and excluded 26 cases in which no growth was obtained on culture. 192 out of 1120 cases (17.14%), showed overall resistance to one or more antituberculous drugs (ATD). Primary drug resistance (PDR) was observed in 161 (14.37%) and acquired drug resistance (ADR) in 31 isolates (2.77%). Of the resistant cases on short course chemotherapy (SCC), single drug resistance was observed in 99 (51.56%), resistance to any two drugs in 63 (32.81%), and three or more drugs in 30 (15.62%) cases. Analysis of resistance to specific drug revealed 26.56% for streptomycin (S), 15.10% for rifampicin (R), 7.29% for isoniazid (H), 2.08% for pyrazinamide (P) and 0.52% for ethambutol (E). Resistance to H and R was present in 4.16% strain and their combination with other drugs resistance was in 16.14% of the drug resistant strains, thus constituting 2.76% of the total sputum positive cases. A group of 26 cases is also discussed, where there was discrepancy in clinical status and bacteriological parameters and treatment for multi-drug resistant tuberculosis (MDR-TB) was instituted.

Larval ecology and mosquito fauna of upper Brahmaputra valley, northeast India

Ninety-one mosquito species in 15 genera were collected from 22 habitat types of Upper Brahmaputra valley in Assam and bordering areas of Arunachal Pradesh. Nineteen species have been recorded for the first time in Assam including seven first records from the northeast region and three first country records. Jaccard's coefficient was used to quantify the similarity between 13 different geographical localities surveyed on the basis of their mosquito fauna. Group average sorting (UPGMA) cluster analysis was used to find out relationship between Jonai, Dhemaji, Dibrugarh, Tinsukia and north Lakhimpur (study zones) on the basis of their mosquito community. Immatures of three malaria vectors incriminated from the northeast India, viz. Anopheles dirus, An. minimus and An. philippinensis were collected exclusively from forest areas. Fourteen potential vectors of Japanese encephalitis incriminated from elsewhere in India were collected during the study.

MANAGEMENT OF LUNG ABSCESS WITH PERCUTANEOUS CATHETER DRAINAGE

Percutaneous catheter drainage was used to treat 12 among 34 cases of lung abscesses, who were refractory to medical therapy, severely ill and high risk cases for surgery. A complete clinical and radiological recovery was achieved in all the cases who underwent catheter drainage, thereby obviating the need for surgery. None of the cases had catheter or procedures related complications. From this study it is inferred that percutaneous transthoracic catheter drainage is a safe and an effective modality of therapy for patients with lung abscess in whom medical therapy has failed and those who are unsuitable for surgery.

MULTIDRUG RESISTANT TUBERCULOSIS - BIOMECHANISM, EPIDEMIOLOGY AND MANAGEMENT STRATEGIES

Muitidrug resistant tuberculosis has shown an alarming increase and this assumes added importance in view of the increasing number of HIV infected patients. This article reviews the biomechanism of resistance and discusses the present stategies that are available and recommended to tackle the rising incidence of tuberculosis due to resistant mycobacteria.

A computed tomographic study of schizophrenia

Fifty schizophrenic patients fulfilling DSM-III-R criteria, and group matched normal healthy controls were selected for the study The case and control groups have been compared in terms of VBR, WSF and WTF. In the study schizophrenics have been divided into positive, negative and mixed subgroups on basis of SAPS and SANS, and these subgroups are compared with each other for VBR, WSF & WTF. Tomographic abnormalities were noted in schizophrenics, particularly with negative and mixed subtypes, when compared to controls.

Revalidation and description of Aedes (Finlaya) Pallirostris from northeastern India (Diptera:Culicidae)

Aedes (Finlaya) pallirostris Edwards is resurrected from synonymy with Aedes (Fin.) formosensis Yamada and the female, male, pupa, and 4th-instar larva are described and compared with closely related species. The synonymy of Finlaya khasiana Barraud is transferred from Ae. formosensis to Ae. pallirostris.

Epidemiology of subperiodic Wuchereria bancrofti infection in the Nicobar Islands, India

Diurnally subperiodic filariasis due to Wuchereria bancrofti has been reported from tribal populations in the Nancowry group of islands in the Andaman and Nicobar Islands, India. This was confirmed in a survey carried out during the monsoon season in 1993. Microfilariae were detected in the peripheral blood throughout a 24 h period with a peak at 18:00. The microfilaria (mf) rate ranged from 1.2% to 18.7%, with a low disease rate (mean = 1.9%). Incidence of mf was low in children less than 10 years old (3.5%), but increased with increasing age. Culex (Culex) quinquefasciatus was present at a very low density. Aedes (Finlaya) niveus and Aedes (Stegomyia) malayensis were the only species commonly biting man. The former was incriminated as a vector, and found naturally infected with W. bancrofti (infection and infectivity rates 1.1% and 0.9% respectively). After experimental feeding on donors, W. bancrofti developed to L3 stage larvae in A. niveus but failed to develop in A. malayensis and A. aegypti.

Detection of haemagglutination inhibition antibodies against Newcastle disease virus in unvaccinated indigenous chickens in Maiduguri, Borno State, Nigeria

An examination of 200 serum samples from unvaccinated indigenous (local) chickens in Maiduguri, Borno State (Nigeria) using the haemagglutination inhibition (HI) test showed 73 sera to be positive and 127 to be negative for antibodies against Newcastle disease virus. The highest antibody titre observed was 1:128. The prevalence rate was higher (46.9%) in adult chickens than in young chickens of less than 12 weeks (23%). Presence of HI antibodies in unvaccinated indigenous chickens indicates that these birds had contracted infection and recovered thereafter.

An immunomodulator in the treatment of schizophrenia : a double-blind study

In a double blind study, the immunomodulator drug levamisole was administered along with chloropromazine to 18 schizophrenic patients, and efficiency of the combination was compared to that of chloropromazine along with placebo administered to 16 schizophrenic patients. The decrease in T suppressor cell count found in both groups at benchmark was found to be corrected in the patients receiving levamisole and this increase in T suppressor cell count was significantly correlated with the improvement in psychosis. The findings provide evidence in favour of the autoimmune hypothesis of schizophrenia.

Excessive polycythaemia of high altitude. Pulmonary function studies including carbon monoxide diffusion capacity

Pulmonary function studies were done in 21 soldiers (low landers) posted at high altitude (average height 4773 metres) for prolonged periods (average 77.09 months), who had developed excessive polycythaemia, mean haemoglobin concentration being 23.06 g/dl. Studies revealed significant reduction in diffusion capacity of lungs which gradually returned to normal on sojourn at low altitudes for 70 days. Both the degree of polycythaemia and reduction in lung diffusion capacity were much more pronounced in smokers than in non-smokers. Vital capacity did not show any difference in these subjects while forced expiratory volume in 1 sec and ratio of forced expiratory volume to vital capacity (FEV1/VC) revealed only obstructive features in smokers.

Pulmonary bullous disease in Marfan syndrome

Two young adults with marfanoid features who had pulmonary bullous disease are presented. One a young soldier, presented with increasing dyspnoea and an enlarging large pulmonary bulla on the right side. The bulla was under tension and was operated on. The other case was a young housewife who also presented with dyspnoea, and was found to have a cardiac murmur and multiple ectopic beats on initial examination. X-Ray chest revealed bilateral pulmonary bullous emphysema. Both the subjects had many features which are accepted as forme fruste of the Marfan syndrome.

Space-spraying with malathion as a supplementary measure for operational malaria control

Entomological studies showed that due to outdoor resting by the vector Anopheles culicifacies as well as poor spray coverage, indoor residual spraying with malathion was ineffective in malarious villages of the Thenpennai riverine tract in Tamil Nadu. Over a 4 yr period during which residual spraying was supplemented with ground applications of malathion space spraying, the slide positivity among patients with fever fell from 21.04 to 1.1 per cent. In mass blood surveys 0.7 per cent persons surveyed at the beginning of the study were positive for the malarial parasite, but no positives were detected in the last survey, in 1984. There was a rising trend in malaria incidence in riverine villages outside the programme.

Enlarging pulmonary histoplasmoma associated with pulmonary tuberculosis

Histoplasmosis is not a frequently reported infection from India. Similarity of its clinical and radiological features with pulmonary tuberculosis, may cause a difficult diagnostic dilemma when the two occur together. We report a case who initially presented with cavitary lesions over right lung responding well to anti tuberculosis chemotherapy but subsequently a small opacity present over the left upper zone showed a relentless increase till it attained a massive size few years later. Operative removal and histopathological examination of the mass confirmed it to be histoplasmoma. She became sputum AFB smear positive and culture negative for a short while during this period and this is explained on the basis of previous reports.

Bilateral recurrent haemorrhagic pleural effusion in asymptomatic chronic pancreatitis

In a case of bilateral recurrent haemorrhagic pleural effusion due to asymptomatic pancreatitis the diagnosis was suggested by the presence of amylase in the pleural fluid when other possible causes had been excluded. Abdominal computed tomography and laparotomy confirmed the diagnosis. No communications could be seen between the peritoneal and pleural space at laparotomy.

Osler-Rendu-Weber disease presenting as recurrent haemoptysis

A young adult male with a short history of recurrent haemoptysis due to vascular malformation of right lung is presented. Lesion was not visible in the chest radiograph, nor on bronchography. CT-scan of thorax, however, showed a bunch of circinate opacities in the upper lobe of the right lung. Histopathological examination of the resected lung tissue confirmed the diagnosis.

Necrobiotic pulmonary nodule leading to pyopneumothorax in a case of rheumatoid arthritis--a rare clinical presentation

A 49-year-old male patient, an active case of sero positive rheumatoid arthritis involving multiple joints with bilateral necrobiotic pulmonary nodules is presented. Initial symptoms were of progressively increasing dyspnoea. The nodule in the right lung subsequently cavitated leading to pyopneumothorax. The diagnosis of rheumatoid lung was confirmed by post-mortem.

Significance of transplant perfusion index in the diagnosis of acute rejection in live related renal allograft recipients

The study was undertaken to assess the usefulness of transplant perfusion index (TPI) in the differential diagnosis of renal allograft dysfunction with special reference to acute rejection. It was observed that the TPI has a sensitivity of 100 per cent and specificity of 98.1 per cent in the diagnosis of acute rejection. It was also observed that the serial values of TPI provided valuable clues and guide in the management of transplant dysfunction and helped in the immediate and long term follow-up of patients with renal allografts.

Malignant mesothelioma in the young (with prosthetic aortic valve an unusual association)

A case of malignant mesothelioma (MM) in a 15 year old boy is reported. He had a prosthetic aortic valve implanted in 1980 at our centre for rheumatic aortic regurgitation. Fever, weight loss and chest pain as initial symptoms suggested possibility of prosthetic valve endocarditis. Dysphagia as another initial symptom was interesting and caused further diagnostic dilemma. Role of Computerised Tomography (CT) scan in diagnosis of MM is highlighted.

A cytogenetic description of a new species of the Anopheles culicifacies complex

Cytogenetic observations on an extensive material of the Anopheles culicifacies complex from the Thenpennai river area, Tamil Nadu, South India show that the populations are made up of four cytologically distinct species. Three of these, labeled A, B and C have already been described. A fourth one, monomorphic for the inversion arrangement +a +b in the X chromosome and il + hl in the second chromosome, is designated as D, another morphologically indistinguishable sibling species. Each sibling species is characterized by a species-specific type of Y-chromosome. Both of these criteria, inversions and Y-chromosomes can be used to distinguish these important malaria vectors.