The effect of mycobacterial virulence and viability on MAP kinase signalling and TNF alpha production by human monocytes

SETTING

The success of Mycobacterium tuberculosis as a human pathogen depends on its ability to tolerate and perhaps manipulate host defense mechanisms.

OBJECTIVE

To determine the induction of tumour necrosis factor-alpha (TNF alpha), a central mediator of immunity, by human monocytes infected with virulent M. tuberculosis, M. leprae and attenuated M. bovis BCG.

DESIGN

Mycobacteria-induced cellular activation pathways of TNF alpha production was investigated using an inhibitor of protein tyrosine kinase (PTKs) and an inhibitor of mitogen-activated protein (MAP) kinases.

RESULTS

TNF alpha production was significantly lower during infection with virulent M. tuberculosis than with BCG and this differential response was independent of mycobacterial viability. TNF alpha production involved the PTK and MAP kinase pathways. Reduced TNF alpha induction by M. tuberculosis was associated with a reduction in the extent and duration of phosphorylation of extracellular-signal regulated kinases (ERK 1/2). Infection with M. leprae triggered low and transient ERK 1/2 activation as well as low TNF alpha production.

CONCLUSION

Maintenance of the differential response in both live and heat-killed preparations suggests that the reduced TNF alpha response associated with virulent mycobacteria is due to differences in the presence of components capable of triggering host pattern recognition receptors, rather than events associated with phagosome trafficking or the active release of intracellular modulators.

Factors affecting unsuccessful referral by the Lady Health Workers in Karachi, Pakistan

OBJECTIVE

To estimate the proportion of patient referral and to identify the factors associated with unsuccessful referral in Karachi, Pakistan.

METHODS

In a cross-sectional survey, a total of 347 patients referred to different health care facilities by the LHWs were interviewed. Data was collected using a structured questionnaire, on demographic characteristics of patients (age, sex, income etc) and potential factors (seriousness of medical condition, distance of health facility, attitude of health center staff etc) that can affect patient referral outcome.

RESULTS

An overall referral rate of 55% was found in this study. Out of a total of 347 patients interviewed, 265 (76.4%) were successful while 82 (23.6%) were unsuccessful referrals. Multivariate logistic regression analysis showed that objection to referral (Adjusted OR, 2.96; CI: 1.44-5.52), never referred before (Adjusted OR, 1.25; CI: 1.34-6.90), not visited the referral site before (Adjusted OR, 4.04; CI: 2.50-6.08) and no knowledge of who to meet at the referral site (Adjusted OR, 1.30; CI: 1.01-2.96) were the factors associated with unsuccessful referral. Other factors found significant were duration of the illness of the patient, anyone not known at the referral site and failure of LHW to follow up.

CONCLUSION

Our study found that a significant proportion of patients seen by the LHWs are referred to different health facilities. Improved management skills of LHWs for simple medical problems would probably reduce the number of referrals. Efforts should also be directed to enhance the communication and counseling skills of LHWs, which may reduce a significant proportion of unsuccessful referrals.

The [99mTc(N)(PNP)]2+ Metal Fragment: A Technetium-Nitrido Synthon for Use with Biologically Active Molecules. The N-(2-Methoxyphenyl)piperazyl-cysteine Analogues as Examples

The incorporation of a bioactive molecule into a nitrido-containing (99m)Tc-complex has been successfully achieved by using the [TcN(PNP)](2+) metal fragment. In this strategy, the strong electrophilic [TcN(PNP)](2+) metal fragment efficiently reacts with bifunctional chelating ligands having a pi-donor atom set, such as N-functionalized O,S-cysteine. The 2-methoxyphenylpiperazine (2-MPP) pharmacophore, which displays preferential affinity for 5HT(1A) receptors, was conjugated to the amino group of cysteine to obtain 2-MPPP-cys-OS, where 2-MPPP is 3-[4-(2-methoxyphenyl)piperazin-1-yl]propionate. The asymmetric Tc(V)-nitrido complexes, [(99g/99m)Tc(N)(PNP)(2-MPPP-cys-OS)] (PNP = PNP3, PNP4), were obtained in high yield (95%), by simultaneous addition of PNP and 2-MPPP-cys-OS ligand to a solution containing a starting (99g)/(99m)Tc-nitrido precursor. A mixture of syn and anti isomers was observed, the latter being the thermodynamically favored species. In vitro challenge experiments using the anti isomers with glutathione and cysteine indicated that no transchelation reaction occurs. Assessment of the in vitro 5HT(1A) receptor-affinity of the technetium complexes revealed that only the anti-PNP4 complex possesses some affinity for the receptor, but displayed negligible brain uptake in biodistribution studies in rats in vivo.

The efficacy of aspirin in patients undergoing infra-inguinal bypass and identification of high risk patients

AIM

Infrainguinal bypass is an effective treatment for critical lower limb ischemia but up to 1/3 of these grafts will occlude within the 1st year. The aim of this audit was to evaluate the efficacy of aspirin in maintaining graft patency and also improving patient survival.

METHODS

In a single audited year (1997) 125 bypasses were carried out. Seventy-nine were on aspirin, 34 on no treatment and 12 were on other agents and hence excluded from analysis. The indication for surgery was critical ischaemia in 101 and disabling claudication in 12. Autologous vein was used in 104 and prosthetic grafts in 9.

RESULTS

The overall 2-year primary graft patency, secondary graft patency and limb salvage were 50%, 71% and 83%, respectively. The 2-year secondary patency in patients with or without aspirin was 73% and 64%, respectively (p<0.12-log rank test). The corresponding patient survival from vascular death in the 2 groups was 73% and 70% (p<0.67-log rank test). Crural/ pedal bypass (51/75 on aspirin) and smoking (51/61 on aspirin) were independent risk factors for graft failure and vascular death respectively whilst those with a previous myocardial infarct (21/28 on aspirin) reached significance in univariate analysis only (p< 0.03).

CONCLUSION

Aspirin was not a significant factor in preventing graft failure or vascular death in patients undergoing bypass for critical limb ischemia. Dual therapy with other antiplatelet agents needs to be considered in such patients particularly those undergoing crural/pedal bypass, smokers and those with a history of previous myocardial infarction.

Frequency and antibiotic susceptibility pattern of mycobacterial isolates from extra-pulmonary tuberculosis cases

OBJECTIVE

To determine the frequency and antimicrobial susceptibility pattern of extra-pulmonary tuberculosis in Rawalpindi.

SETTING

Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi.

METHODS

Between September 2000 and August 2002, 899 pulmonary and 460 extra-pulmonary specimens from suspected cases of tuberculosis were examined. The radiometric BACTEC 460 TB system was used for culture and antimicrobial susceptibility testing.

RESULTS

Mycobacteria were isolated from 291 pulmonary specimens and 98 extra-pulmonary specimens. The frequency of extra-pulmonary tuberculosis was 25.2%. The commonest source of isolation was pus (44.9%, frequency 11.3%), followed by lymph nodes (13.3%, frequency 3.3%) and pleural fluid (13.3%, frequency 3.3%). We tested the anti-microbial susceptibility of the isolates to the four first line anti-tuberculous drugs, rifampicin, isoniazid, streptomycin and ethambutol. Of the extra-pulmonary isolates 13.3% were resistant to a single drug, 21.4% were multi-drug resistant and 9.2% were resistant to all the four drugs.

CONCLUSION

Increased awareness of the magnitude of the problem posed by extra-pulmonary tuberculosis is required so that appropriate control measures can be adopted.

Microtibial embolectomy

BACKGROUND

microtibial embolectomy is an important technique in cases of limb threatening acute arterial occlusion affecting native crural and pedal vessels. It is particularly useful when thrombolysis is contraindicated or ineffective as in "trash foot".

METHODS

in order to evaluate the efficacy of this technique, a retrospective case note review was carried out for patients undergoing microtibial embolectomy from 1990 to 1999. Data collected included the causes and degree of ischaemia, additional procedures required, vessel patency, limb salvage and complications encountered.

RESULTS

twenty-two limbs underwent exploration of the crural/pedal vessels with ankle level arteriotomies under local anaesthetic in 12 cases, general anaesthetic in nine and epidural in one. The causes of ischaemia were cardiac emboli (8), "trash foot" (7), emboli from aortic and popliteal aneurysms (3) and thrombotic occlusion of crural vessels (4). The vessel patency rate was 69% and limb salvage rate 62% (13/21) up to 5-years follow-up. Six of the seven cases with "trash foot" were salvaged while one required an amputation at 3-months post-operatively. The 30-day mortality was 22% (5/22).

CONCLUSIONS

microtibial embolectomy is effective in acute occlusion of the crural/pedal arteries including cases of "trash foot", offering limb salvage to a worthwhile proportion of cases.

Neonatal sepsis: high antibiotic resistance of the bacterial pathogens in a neonatal intensive care unit in Karachi

OBJECTIVE

To study the bacterial pathogens causing neonatal sepsis and their sensitivity pattern so that guidelines can be prepared for empirical antibiotic therapy.

SETTING

The study was conducted in the neonatal intensive care unit (NICU) at PNS Shifa (Naval Hospital), Karachi during January 1997 to June 1999.

METHODS

Blood specimens for culture were drawn from 520 newborns admitted in a NICU with sepsis. The specimens were inoculated into brain heart infusion broth. Subcultures were performed on days 1, 2, 3, 5, 7 and 10. The isolates were identified by standard biochemical tests. Antibiotic resistance pattern of the isolates was studied by Modified Kirby Baur disc diffusion technique.

RESULTS

A total of 212 organisms were isolated. These included Staphylococcus aureus (n = 65), Klebsiella pneumoniae (n = 73), Acinetobacter baumannii (n = 23), Escherichia coli (n = 22), Enterobacter cloacae (n = 18), Citrobacter diversus (n = 5), Pseudomonas aeruginosa (n = 4) and group B Streptococcus (n = 2). On antibiotic sensitivity testing, 61.54% of Staphylococcus aureus isolates were found to be methicillin resistant. Susceptibility to the other common drugs was also quite low while 89.23% of these were susceptible to amikacin and 100% to vancomycin. More than 90% gram negative rods were resistant to ampicillin and co-trimoxazole. Resistance to gentamicin was as high as 90.4% for Klebsiella pneumoniae; 60.87% for Acinetobacter baumannii. Resistance to the third generation cephalosporins and the quinolone tested (ciprofloxacin) varied between 25-75%. Majority of the isolates were susceptible to meropenem and amikacin.

CONCLUSION

In view of the isolation of highly antibiotic resistant organisms, vancomycin in combination with amikacin or a carbapenem is the drug of choice for empirically treating neonatal sepsis.

Effect of zinc on hepatic lipid peroxidation and antioxidative enzymes in ethanol-fed rats

A 3-ml aliquot of 30% ethanol was fed daily to normal as well as zinc-treated (227 mg l(-1)) rats for periods of 2, 4 and 8 weeks. A highly significant increase in the levels of hepatic lipid peroxidation was observed in ethanol-fed rats after 4 and 8 weeks of treatment. On the other hand, the levels of lipid peroxidation came down significantly following ethanol feeding to zinc-treated rats. The activities of glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD) in liver were elevated significantly after ethanol administration to rats for durations of 2, 4 and 8 weeks. Interestingly, zinc treatment to rats given ethanol was able to bring down the elevated levels of SOD, catalase and GPx to within normal limits, However, zinc administration alone did not cause any significant alteration in the activities of these antioxidative enzymes.

The Cardiff sib-pair study: suicidal ideation in depressed and healthy subjects and their siblings

Depression is associated with high rates of suicidal ideation, which varies in intensity from transient thoughts of wishing to be dead to the making of plans and, Finally, to attempts to kill oneself. There is limited evidence from family, twin, and adoption studies that completed suicide is familial and has a genetic etiological component. However, it is unclear whether suicidal ideation is also familial. The familiality of suicidal ideation has been examined in the subjects who participated in the Cardiff Depression Study, namely, 108 depressed probands. their nearest-aged siblings, and 105 healthy control subjects and their siblings. The study showed that 66% of depressed subjects had experienced suicidal ideation in the week prior to the interview, and that this was significantly associated with recurrent illness. Suicidal ideation was not shown to be familial. However, somewhat surprisingly, 6% of healthy, never-depressed subjects admitted to having had transient suicidal thoughts. Suicidal ideation was significantly associated with high neuroticism and psychoticism scores and severe threatening life events.

In vivo near-infrared fluorescence imaging of osteoblastic activity

In vertebrates, the development and integrity of the skeleton requires hydroxyapatite (HA) deposition by osteoblasts. HA deposition is also a marker of, or a participant in, processes as diverse as cancer and atherosclerosis. At present, sites of osteoblastic activity can only be imaged in vivo using gamma-emitting radioisotopes. The scan times required are long, and the resultant radioscintigraphic images suffer from relatively low resolution. We have synthesized a near-infrared (NIR) fluorescent bisphosphonate derivative that exhibits rapid and specific binding to HA in vitro and in vivo. We demonstrate NIR light-based detection of osteoblastic activity in the living animal, and discuss how this technology can be used to study skeletal development, osteoblastic metastasis, coronary atherosclerosis, and other human diseases.

Treatment of traumatic brain injury in female rats with intravenous administration of bone marrow stromal cells

OBJECTIVE

To study the effect of bone marrow stromal cells administered intravenously to female rats subjected to traumatic brain injury.

METHODS

We injected marrow stromal cells harvested from male rat bone marrow (n = 24) into the tail vein of the female rat (n = 8) 24 hours after traumatic brain injury; the rats were killed at Day 7 or 14 after treatment. The neurological function of the rats was evaluated using the rotarod test and the neurological severity score. The distribution of the male donor cells in brain, heart, lung, kidney, liver, muscle, spleen, and bone marrow of the female recipient rats was measured by identifying Y chromosome-positive cells using fluorescent in situ hybridization.

RESULTS

We found that marrow stromal cells injected intravenously significantly reduced motor and neurological deficits compared with control groups by Day 15 after traumatic brain injury (P < 0.05, analysis of covariance for repeated measures). The transplanted cells preferentially engrafted into the parenchyma of the injured brain and expressed the neuronal marker NeuN and the astrocytic marker glial fibrillary acidic protein. Marrow stromal cells were also found in other organs in female rats subjected to traumatic brain injury without any obvious adverse effects.

CONCLUSION

These data suggest that the intravenous administration of marrow stromal cells may be a promising therapeutic strategy that warrants further investigation for patients with traumatic brain injury.

Effects of endosulfan on intestinal functions in protein-malnourished rats

In rats fed 18% protein diet, administration of endosulfan (2mg/kg body weight daily for 7 days) significantly decreased the brush border sialic acid and increased the hexoses contents. The intestinal uptake of glucose was increased while that of glycine and calcium was reduced. Brush border enzymes and lipids were not affected. However, in protein malnourished rats (fed 8% protein) exposed to endosulfan, brush border sucrase and peptidase activities were enhanced, while alkaline phosphatase activity was decreased compared to untreated malnourished animals. Membrane sialic acid content was low while fucose and cholesterol levels were augmented in endosulfan fed malnourished animals. The uptake of glucose and glycine was elevated under these conditions. These results Suggest that the nutritional status of the animals has an important bearing on thc susceptibility of intestinal tissue to endosulfan toxicity in rats.

[99mTc]oxotechnetium(V) complexes amine-amide-dithiol chelates with dialkylaminoalkyl substituents as potential diagnostic probes for malignant melanoma

[99mTc]oxotechnetium(V) complexes of amine-amide-dithiol (AADT) chelates containing tertiary amine substituents were synthesized and shown to have affinity for melanoma. For complexation the AADT-CH2[CH2]nNR2 (n = 1, 2; R = Et, n-Bu) ligand was mixed with a [99mTc]oxotechnetium(V)-glucoheptonate precursor to make the AADT-[99mTc]oxotechnetium(V) complexes in nearly quantitative yield. Structurally analogous nonradioactive oxorhenium(V) complexes were also synthesized and characterized. In vitro sigma-receptor affinity measurements indicate these complexes to possess sigma-affinity in the low micromolar range with K(i) values in the 7.8-26.1 and 0.18-2.3 microM range for the sigma1- and sigma2-receptors, respectively. In vitro cell uptake of the 99mTc complexes in intact B16 murine melanoma cells at 37 degrees C after a 60-min incubation ranged from 12% for complex 2 (n = 1, R = n-Bu) to 68% for complex 4 (n = 2, R = n-Bu). In vivo evaluation of complexes 1-Tc-4-Tc in the C57Bl/B16 mouse melanoma model demonstrated significant tumor localization. Complex 1-Tc (n = 1, R = Et) displayed an in vivo tumor uptake of 7.6% ID/g at 1 h after administration with initial melanoma/blood (M/B), melanoma/spleen (M/S), and melanoma/lung (M/L) ratios >4; these ratios increased to 10.8, 10.1, and 7.3, respectively, at 6 h. While complex 3-Tc (n = 3, R = Et) had an initial tumor uptake of 3.7% ID/g 1 h after administration with M/B, M/S, and M/L ratios >2, a greater tumor retention and slightly faster clearance from nontumor-containing organs resulted in M/B, M/S, and M/L ratios of 19.1, 19.1, and 12.7, respectively, at 6 h. The high tumor uptake and significant tumor/nontumor ratios indicate that such small technetium-99m-based molecular probes can be developed as in vivo diagnostic agents for melanoma and its metastases.

Age related effects of organochlorine insecticide lindane on intestinal brush border membrane in rats

The effect of oral administration of lindane (gamma-HCH) has been studied on the intestine in 10-day, 20-day and 100-day old rats. In 10 day-old suckling pups exposed to lindane, there was a significant decrease in the activities of sucrase (29%), lactase (20%) and that of alkaline phosphatase (24%) compared to control. Sialic acid content of the brush borders was significantly decreased (29%) in 10-day old as well as in 20- and 100-day old rats (20 and 25% respectively), while fucose content of the membranes was significantly enhanced in all the age groups upon pesticide treatment. Among the brush border lipids, cholesterol content was significantly increased in all the age groups studied, the maximum increase of 35% being observed in 10-day-old rats. Membrane phospholipids were also increased in 20- and 100-day old animals (22% each) on lindane exposure. The present studies indicated that brush border membranes of suckling rat intestine were more susceptible to pesticide induced changes compared to older animals.

Ossification of autologous pericranium used in duraplasty. Case report

Pericranium is frequently used in duraplasty and is considered superior to the many other alternatives because of its easy availability and because it offers a watertight dural closure while minimizing the problems of adhesion, infection, and rejection. Although the osteogenic potential of all periosteal tissues is recognized, a review of the literature did not reveal a reported case of osseous formation following use of pericranium for duraplasty. The authors report the case of a 17-year-old man who presented with a self-inflicted gunshot wound to the head. He was obtunded, but moving all extremities purposefully. Computerized tomography scanning demonstrated bifrontal injury. A bicoronal craniotomy with debridement was performed on an emergency basis, with vascularized pericranium used for a duraplasty. Follow-up cranioplasty demonstrated significant ossification of the pericranium 5 months after the original surgery. Pericranium is an attractive material for duraplasty; however, its osteogenic potential may interfere with future cranioplasty and cosmesis. This may be especially relevant in young persons.

Intraarterial administration of marrow stromal cells in a rat model of traumatic brain injury

To test the efficacy of various delivery routes of stem cells to treat cerebral injury, we investigated the parenchymal distribution of marrow stromal cells (MSCs) injected into the internal carotid artery (ICA) of the adult rat after traumatic brain injury (TBI). Bromodeoxyuridine (BrdU)-labeled MSCs were injected via the ipsilateral ICA at 24 h after TBI. Using histology and immunohistochemistry, the distribution of implanted MSCs was analyzed at 7 days after transplantation. Four groups (n = 4/group) were studied: group 1, animals transplanted with MSCs cultured with NGF and BDNF at 24 h after TBI; group 2, animals transplanted with MSCs cultured without NGF and BDNF; group 3, animals injected with a placebo, phosphate buffered saline into the ICA at 24 h after TBI; and group 4, rats subjected to TBI only. In groups 1 and 2, BrdU-positive cells were localized to the boundary zone of the lesion, corpus callosum and cortex of the ipsilateral hemisphere. The number of BrdU-positive cells was significantly higher in the ipsilateral hemisphere than in the contralateral hemisphere. More MSCs infused intraarterially engrafted in group 1 (18.9%) than in group 2 (14.4%, p < 0.05). Using double staining, BrdU-positive cells expressed MAP-2, NeuN, and GFAP in both groups 1 and 2, with this expression being greater in group 1 and the difference between two groups reaching statistical significance in case of MAP-2. Our data suggest that intraarterial transplantation of MSCs is a viable route for the intracerebral administration of MSCs for the treatment of TBI, since MSCs infused intraarterially after TBI survive and migrate into the brain. Some implanted MSCs express proteins specific to neurons and astrocytes. The addition of NGF and BDNF promote migration of MSCs into the brain and subsequent expression of neuronal protein MAP-2.

Formation of surfactant-like-particle in rat intestine following chronic ethanol feeding

Ethanol feeding to rats daily for 40 days induces the secretion of surfactant-like-particles in intestine. The isolated lipoprotein particles were enriched with alkaline phosphatase activity and had high phosphatidylcholine content. There was no difference in disaccharidases activities associated with the particles from control and ethanol fed rats. These results suggest that ethanol induced surfactant-like-particles in rat intestine.

TmDOTA-: a sensitive probe for MR thermometry in vivo

The lanthanide complex, thulium 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (TmDOTA-), has been investigated as an agent for MR thermometry in vivo. The chemical shifts of the TmDOTA- protons were highly sensitive to temperature at a clinically relevant field strength, yet insensitive to pH and the presence of Ca2+. Given the excellent stability of lanthanide-DOTA complexes and high thermal sensitivity, TmDOTA- is expected to be a good candidate for MR thermometry in vivo.

Activity of brush border membrane enzymes in proximal jejunum of portal hypertensive rats

PURPOSE

Malabsorption accompanies portal hypertension, especially when associated with chronic liver disease. The development of portal hypertension is accompanied by significant alterations in the splanchnic microcirculation. In this study, the effect of extrahepatic and intrahepatic portal hypertension on brush border membrane enzymes was estimated.

METHODS

Portal hypertension was induced in rats by partial portal vein ligation (PPVL) (n = 6) and common bile duct ligation (CBDL) (n = 6), and the activity of sucrase, lactase, alkaline phosphatase, and leucine aminopeptidase (LAP) in the intestinal homogenate was measured.

RESULTS

Intrasplenic pulp pressure (ISPP) (in cm of saline) was found to be elevated in PPVL (21.3 +/- 1.47) and CBDL animals (21.5 +/- 1.79) as compared with findings in their respective sham-operated controls (12.74 +/- 0.86, 11.83 +/- 1.04). Only sucrase and LAP activity was significantly elevated (P < 0.05) in the PPVL group. No changes were observed in the CBDL group.

CONCLUSION

Only sucrase and LAP activities were increased in PPVL rats.

Sensation-seeking, life events and depression. The Cardiff Depression Study

BACKGROUND

The relationship between adversity and genetic risk factors in depression could be mediated by familial 'hazard prone' traits, as reflected in high levels of sensation-seeking.

AIMS

To examine whether high sensation-seeking scores are associated with more adverse life events resulting in depression.

METHOD

In a sib-pair design, 108 probands with depression and their siblings and 105 healthy control subjects and their siblings were compared for psychopathology, life events and scores on the Sensation-Seeking Questionnaire (SSQ).

RESULTS

The SSQ scores were correlated negatively with depression, were familial and were correlated positively with less severe events, but not the severe events typically associated with depressive onsets.

CONCLUSIONS

The SSQ measures a familial personality trait and depression is associated with lower scores. Although high sensation-seeking is associated with a higher rate of life events, these carry little threat.

Blood stream infections in a medical intensive care unit: spectrum and antibiotic susceptibility pattern

OBJECTIVE

To determine the type and sensitivity pattern of causative organisms of septicaemia in intensive care unit, to prepare a guideline for empirical antibiotic therapy.

SETTING

Department of pathology and adult medical intensive care unit, PNS SHIFA (Naval Hospital), Karachi.

METHODS

The study was conducted from January 1997 to June 1999. Blood specimens for culture were drawn from patients who developed symptoms/signs of bacteraemia/septicaemia 48 hours or more after admission in medical ICU. The specimens were inoculated into Brain Heart Infusion broth. Subcultures were done on days 1,2,3,5,7 and 10. The isolates were identified by standard biochemical tests. Antibiotic susceptibility pattern of the isolates was studied by Modified Kirby Baur method.

RESULTS

Eighty-six aerobic organisms were isolated. They included Staphylococcus aureus(n = 34), Pseudomonas aeruginosa (n = 13), Escherichia coli and Enterobacter spp(n = 9 each), Klebsiella pneumoniae(n = 8), Acinetobacter spp and Serratia spp(n = 5 each), Citrobacter diversus(n = 2) and Proteus vulgaris(n = 1). On antibiotic susceptibility testing, 48.18% Staphylococcus aureus isolates were methicillin resistant. Susceptibility to other common drugs was also quite low while 100% of these were susceptible to vancomycin and amikacin. In case of gram negative rods more than 80% were resistant to ampicillin and cotrimoxazole. Susceptibility to gentamicin was as low as 25% for Klebsiella pneumoniae to 44.4% in case of Escherichia coli. Susceptibility to the third generation cephalosporins and the quinolone tested (ciprofloxacin) varied between 50-75%. All these isolates except Pseudomonas aeruginosa were susceptible to imipenem and amikacin.

CONCLUSION

In view of the isolation of antibiotic resistant organisms, vancomycin in combination with amikacin or imipenem are the drugs of choice for empirically treating blood stream infections in ICU. Infection control procedures and antibiotic control policies can help to tackle this problem.