Etiological Profile of Infectious Fever - Bacterial and Parasitical.

INTRODUCTION : The concept of "Fever of unknown", "undiagnosed", "unexplained origin" or "pyrexia of unknown origin" evolved in the medical literature from 1950. FUO is a challenging medical problem. Fever is defined as an elevation of core temperature above normal, i.e. > 37.8oC due to resetting of the thermoregulatory centre in medulla. The cause can vary from minor brief illness to life threatening infections, malignancy or autoimmune disease. The spectrum of FUO seems to be determined by geographic and economic factors, and it appears to change in time. Categorisation of fever including the duration and the presence of specific localising signs have been difficult because of areas of overlap. In most patients with fever lasting one or two weeks, the underlying disorder is soon discovered or the patient recovers spontaneously. In other patients however, fever continues for two or three weeks during which time physical examination, chest x-ray films, blood tests and routine cultures do not reveal the cause of fever. In these cases the provisional diagnosis of fever of unknown origin (FUO) is made. AIMS AND OBJECTIVES : 1. To study the percentage of microbial infections in FUO cases attending Govt. General Hospital, Chennai. 2. To identify the bacterial agents causing fever. 3. To findout the parasites causing fever. 4. To detect the presence of leptospiral antigen by DFM, culture and PCR and antibody detection by serological methods. 5. To compare the blood smear study with rapid diagnostic test for the identification of malarial parasite. 6. To carry out blood smear study for the detection of filariasis, babesiosis, leishmaniasis and toxoplasmosis. 7. To compare the conventional method with rapid test for antibody detection in enteric fever. 8. To identify the etiological agents causing urinary tract infection, pneumonia, bacteremia and to determine their antibiotic susceptibility pattern. 9. To carry out serological tests for antibody detection in typhus fever and brucellosis. MATERIALS AND METHODS : The study included 124 patients, admitted to the Government General Hospital, Chennai with fever of 1 week and more duration and of the age group 12 years and above. Only bacterial and parasitic causes of the FUO infections were included in this study. Immuno deficient patients and patients who were treated already with antibiotics were excluded from this study. Viral and fungal causes of FUO were not investigated in the present study. Detailed history was obtained from all the patients and a complete clinical examination was done. Patients were subjected to investigations based on their clinical picture. The data collected from the patients were documented in a proforma. All 124 patients were subjected to the basic investigations irrespective of the provisional diagnosis. Relevant data were collected in the prescribed proforma along with socio-economic details. RESULTS : Total number of FUO cases taken up for study – 124. It is evident that among infectious diseases the commonest cause of fever was found to be leptospirosis followed by malaria. The other significant causes were enteric fever, urinary tract infection and pneumonia. In majority of cases taken in the study, fever had lasted for 1-2 weeks. Very few cases had fever lasting for more than a month. More men than women reported with fever (except tuberculosis & UTI). In the present study, most of the cases with fever were between the age group 21 and 60 years. Fever, myalgia and conjunctival suffusion were the common clinical features seen in leptospirosis cases. Jaundice was present in 46% of cases. Antigen was detected only in 4 cases, antibody was detected in all the 28 cases. Predominant sero group was Icterohaemorrhagiae 14 (53.8%) In the peripheral blood smear 18 cases were positive for malaria and other parasites were found to be negative. All the malaria cases presented with fever and chills. Splenomegaly was present in 72.2% cases. Malaria was diagnosed by peripheral smear method and by rapid method - PLDH. Both tests were equally effective in the diagnosis of Malaria. CONCLUSION : Infections (61.3%) remain the most important cause of FUO in India, confirming the trends found earlier in other studies. Leptospirosis (22.6%) followed by malaria (14.5%) and enteric fever (6.5%) were the common infections diagnosed. L.icterohaemorrhagiae was the predominant sero group. The rapid diagnostic tests used in comparison with the conventional methods in the diagnosis of malaria and enteric fever were equally good. The rapid tests were simple, sensitive and easy to perform and could be recommended for early diagnosis in both urban and field studies. E. coli, Klebsiella pneumoniae, Staph. aureus and Proteus vulgaris were the etiological agents of UTI, pneumonia and bacteremia. In majority of isolates the drug of choice were Ciprofloxacin followed by Amikacin. Babesiosis, Leishmaniasis, Typhus fever, Toxoplasmosis, Filariasis and Amebiasis were not detected in the present study. This study indicates that with the appropriate use of new sero diagnositic and newer microbilogical methods will result in increased number of cases being diagnosed early and appropriate treatment can be given. The role of viruses and fungi have not been touched upon in this study. Further studies of other etiological agents will help in diagnosing the other causes of infectious fever

Keratinase production by Bacillus megaterium RS1 using the statistical tool central composite design

Keratinase producing bacterium Bacillus megaterium RS1 was obtained from feather dumping site of Rajapalayam. The optimal level of the key variables (starch, feather meal, calcium chloride) was used to determine the effect of their interactions on keratinase production using the statistical tool [(Central composite design (CCD) of response surface methodology (RSM)]. The second-order quadratic model with the optimum conditions [(starch (1%); feather meal (3%) and calcium chloride (0.02%)] was used. The nearness of the coefficient of determination (R2 = 1.0000) to 1 ensures the satisfactory adjustment of the quadratic model to the experimental data. The maximum keratinase production was 142.9 U/ml.Keywords: Keratinase, Central composite design (CCD), response surface methodology (RSM), Bacillus megaterium RS1 starch, feather meal, calcium chloride

Interactive Effect of Botanicals and <i>Bacillus thuringiensis</i> Subsp <i>Israelensis</i> on <i>Culex quinquefasciatus</i> Say

1068-1076Strains of Culex quinquefasciatus Say were selected for testing insecticidal toxins produced by Bacillus thuringiensis Subsp Israelensis Berliner, Neem oil (Azadirachta indica) and Pongamia oil (Pongamia pinnata), singally as well as in combination. The larval, pupal and adult mortality increased significantly with increasing levels of Bii, neem oil and pongamia oil, either alone or in combination. In contrast, combination of neem oil and pongamia oil with Bii resulted in a synergestic of potentiate effect on larvae of C. quinquefasciatus. Sublethal concentrations of neem oil pongamia oil and Bii applied singally or in combination, reduce the fecundity and retarded the larval growth of C. quinquefasciatus . The emergence of adults was also studied woth Bii, neem oil and pongamia oil treatment alone and in combination. The treatment with Bii, neem oil pongamia oil affected the emergence of C. quinquefasciatus

Comparative study on the antivibrio activity of <i style="mso-bidi-font-style:normal">vibrio</i> species isolated from <i style="mso-bidi-font-style:normal">Penaeus monodon,</i> <i style="mso-bidi-font-style:normal">sillago sihama</i> against spices.

934-936Totally 55 <i style="mso-bidi-font-style: normal">Penaeus monodon samples were collected and plated on TCBS agar medium 35 samples showed colonies on TCBS agar. Both yellow and green colours were observed. In Sillago sihama, 45 samples collected and plated on TCBS agar among the samples 25 sample showed colonies on agar medium. Canned sea food 25 sample plated 15 showed colonies on TCBS agar plates. Among the total isolates P. monodon showed the presence of 3 Vibrio species namely V. cholerae, V. parahaemolyticus and V. harveyi. <i style="mso-bidi-font-style: normal">S. sihama showed the presence of <i style="mso-bidi-font-style: normal">V. cholerae, V. parahaemolyticus and V. harveyi. From the canned food only two species V. cholerae and V. parahaemolyticus were characterized. Among the antivibrio activity of the selected plants, Cumin showed the maximum zone of inhibition against <i style="mso-bidi-font-style: normal">V. parahaemolyticus. This study revealed that the isolates were susceptible against the plant extract