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R K Gupta,
R Awasthi,
R K Garg,
N Kumar,
P K Gupta,
A K Singh,
P Sahoo,
V K Paliwal, K N Prasad,
C M Pandey,
R K S Rathore
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ABSTRACT: BACKGROUND AND PURPOSE:Epileptogenesis in NCC is associated with perilesional inflammation and disruption in BBB. We quantified BBB in different stages of NCC by using DCE-MR imaging to look for the differences in perfusion indices and to correlate these indices with serum MMP-9 expression.MATERIALS AND METHODS:DCE-MR imaging along with conventional MR imaging was performed in 57 single cysticercous brain lesions to quantify the k(ep), K(trans), and v(e) around the lesions, which were in different stages of evolution. There were 6 lesions in the vesicular stage and 17 lesions each in the colloidal, granular-nodular, and calcified stages. Serum MMP-9 was quantified from all patients, whereas perfusion indices were quantified from all stages except for the vesicular stage.RESULTS:We observed significant differences among the 3 stages of NCC in serum MMP-9 expression as well as DCE-derived k(ep) values. In addition, k(ep) showed a strongly significant positive correlation with MMP-9 expression when modeled with the individual stage of the disease as well as with all stages when pooled together. Other DCE-derived hemodynamic and pharmacokinetic parameters showed inconsistent differences with each stage of the disease. The correlation of DCE-derived parameters with serum MMP-9 expression and edema volume also showed inconsistency with the stage of the disease.CONCLUSIONS:We conclude that k(ep) correlates best with serum MMP-9 expression among the pharmacokinetic indices and most closely represents the degree of BBB breakdown, which is highest in the colloidal stage and lowest in the calcified stage. k(ep) may be used as a noninvasive image biomarker of BBB breakdown in different stages of NCC.
American Journal of Neuroradiology 11/2012; · 2.93 Impact Factor
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ABSTRACT: Calcified cysticercus larva with perilesional abnormality is thought to be responsible for seizures in patients with neurocysticercosis (NCC). However, it is not well understood why some calcified cysts are associated with seizures even without perilesional abnormality.
The study group consists of 30 subjects from an ongoing survey for disease burden estimation of a swine farming community who had a single calcified lesion without any perilesional abnormality with or without presentation of seizures. Each group consisted of 15 patients with calcified cysts and was labeled as asymptomatic and symptomatic. We performed dynamic contrast-enhanced (DCE) MRI on all these subjects and determined serum matrix metalloproteinase-9 (MMP-9) levels and MMP-9 gene polymorphisms.
DCE-MRI-derived rate transfer constant (k(ep)) and serum MMP-9 levels showed significant differences between symptomatic and asymptomatic subjects. We observed an increase in the MMP-9 levels, k(ep), and the volume transfer coefficient (k(trans)) in these lesions. We also observed a significant increase in MMP-9 (R279Q) gene polymorphism in symptomatic subjects compared with asymptomatic and control subjects.
Perilesional inflammation, which varies from symptomatic to asymptomatic subjects, can be quantified using DCE-MRI in calcified cysticercosis and may help distinguish these 2 groups with similar imaging findings. The observed increase in k(ep) with serum MMP-9 levels suggests that the former may serve as a biomarker of MMP-9 levels in these subjects. The significant MMP-9 (R279Q) gene polymorphism in symptomatic subjects might explain the differences in the observed DCE-MRI indices between symptomatic and asymptomatic subjects.
Neurology 02/2012; 78(9):618-25. · 8.31 Impact Factor
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ABSTRACT: To correlate phase and R2* derived from susceptibility-weighted magnetic resonance imaging (MRI) with computed tomography-Hounsfield (CT-HU) values in calcified neurocysticercosis and to evaluate phase imaging in the assessment of calcified neurocysticercosis.
Thirty-five patients with 52 calcified lesions underwent both CT and MRI. Phase and R2* were calculated from multi-echo 3D-T2-star-weighted-angiography data. MRI and CT data were coregistered using mutual information. Spearman's correlation was performed between quantitative phase and CT-HU and R2* values. The Mann-Whitney U-test was used to see differences between CT-HU and R2* values from corresponding positive and negative phase regions.
The median values of CT-HU and R2* from regions with positive and negative phase were found to be 142.10 (range: 41.89-491.75) and 68.5/sec (range: 20-110/sec) and 137.30 (range: 30.83-458.88) and 69/sec (range: 0-110/sec), respectively. There was a significant correlation of positive phase values with corresponding CT-HU and R2* values. In addition, there was a significant correlation of R2* and CT-HU with negative phase values.
We conclude that there is a significant correlation between negative and positive phase with CT-HU and R2* values, suggesting that the CT hyperdense lesion may have both calcium and other minerals, which can be differentiated using phase imaging. Conventional MRI should include phase imaging to detect calcified neurocysticercosis.
Journal of Magnetic Resonance Imaging 11/2011; 34(5):1060-4. · 2.70 Impact Factor
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B. Roy MSc,
S. Verma MSc,
R. Awasthi MSc,
R.K. Rathore PhD,
R. Venkatesan PhD,
S.A. Yoganathan MSc,
J.K. Maria Das PhD,
K.N. Prasad MD,
R.K. Gupta MD,
B. Roy,
S. Verma,
R. Awasthi,
R.K. Rathore,
R. Venkatesan,
S.A. Yoganathan,
J.K. Maria Das, K.N. Prasad,
R.K. Gupta
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ABSTRACT: Purpose:To correlate phase and R2* derived from susceptibility-weighted magnetic resonance imaging (MRI) with computed tomography-Hounsfield (CT-HU) values in calcified neurocysticercosis and to evaluate phase imaging in the assessment of calcified neurocysticercosis.Materials and Methods:Thirty-five patients with 52 calcified lesions underwent both CT and MRI. Phase and R2* were calculated from multi-echo 3D-T2-star-weighted-angiography data. MRI and CT data were coregistered using mutual information. Spearman's correlation was performed between quantitative phase and CT-HU and R2* values. The Mann–Whitney U-test was used to see differences between CT-HU and R2* values from corresponding positive and negative phase regions.Results:The median values of CT-HU and R2* from regions with positive and negative phase were found to be 142.10 (range: 41.89–491.75) and 68.5/sec (range: 20–110/sec) and 137.30 (range: 30.83–458.88) and 69/sec (range: 0–110/sec), respectively. There was a significant correlation of positive phase values with corresponding CT-HU and R2* values. In addition, there was a significant correlation of R2* and CT-HU with negative phase values.Conclusion:We conclude that there is a significant correlation between negative and positive phase with CT-HU and R2* values, suggesting that the CT hyperdense lesion may have both calcium and other minerals, which can be differentiated using phase imaging. Conventional MRI should include phase imaging to detect calcified neurocysticercosis. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging 10/2011; 34(5):1060 - 1064. · 2.70 Impact Factor
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ABSTRACT: DWI by using higher b-values provides tissue diffusivity with less T2 shinethrough effect. VCD in the abscess cavity correlates with ADC values. The purpose of this study was to investigate which b-value-derived ADC correlates better with VCD.
Thirty patients with brain abscess underwent conventional MR imaging and DWI with b = 1000, 2000, and 3000 s/mm(2) on a 3T MR imaging scanner. ADC values were quantified by placing regions of interest inside the abscess cavity in all sections where the lesion was apparent on coregistered ADC maps derived from different b-values. VCD was measured on pus aspirated.
An increase in b-value was associated with a decrease in ADC values in normal parenchyma as well as in the abscess cavity. The most significant negative correlation of VCD was observed with b = 3000 s/mm(2) (r = -0.98, P = .01).
VCD in the abscess cavity can be best assessed at b = 3000 s/mm(2) secondary to the reduction in the T2 shinethrough effect. DWI with b = 3000 s/mm(2) is of promising value in the assessment of the therapeutic response of brain abscess.
American Journal of Neuroradiology 09/2011; 32(11):2120-5. · 2.93 Impact Factor
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ABSTRACT: SSPE is a persistent infection of the central nervous system caused by the measles virus. The correlation between the clinical staging and conventional MR imaging is usually poor. The purpose of this study was to determine whether tract-specific DTI measures in the major white mater tracts correlate with clinical grades as defined by the Jabbour classification for SSPE.
Quantitative DTT was performed on 20 patients with SSPE (mean age, 9 years) and 14 age- and sex-matched controls. All patients were graded on the basis of the Jabbour classification into grade II (n=9), grade III (n=6), and grade IV (n=5) SSPE. The major white matter tracts quantified included the CC, SLF, ILF, CST, CNG, SCP, MCP, ICP, ATR, STR, and PTR.
Although a successive decrease in mean FA values was observed in all the fiber tracts except for the SCP and ICP, moving from controls to grade IV, a significant inverse correlation between clinical grade and mean FA values was observed only in the splenium (r=-0.908, P<.001), CST (r=-0.663, P=.013), SLF (r=-0.533, P=.050), ILF (r=-0.776, P=.001), STR (r=-0.538, P=.047), and PTR (r=-0.686, P=.035) fibers. No significant correlation of mean MD values from these white matter tracts was observed with clinical grades of the disease.
We conclude that the grade of encephalopathy correlates inversely with the tract-specific mean FA values. This information may be valuable in studying the disease progression with time and in assessing the therapeutic response in the future.
American Journal of Neuroradiology 02/2011; 32(4):714-20. · 2.93 Impact Factor
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ABSTRACT: We studied the bacterial aetiology and antibiotic sensitivity pattern of diabetic foot ulcers in India.
Records of 447 hospitalised patients between 1991 and 2008 were retrospectively analysed between two time periods (before and after 1999) to compare bacterial aetiology and antimicrobial sensitivity patterns. The first three consecutive cultures from the same wound during treatment were evaluated.
Of 1,632 cultures, 66% were polymicrobial, 23% monomicrobial and 11% sterile. In the monomicrobial group, 14% (n = 228) of cultures were Gram-negative, whereas 9% (n = 147) were Gram-positive. The most common pathogens in the first culture were Pseudomonas aeruginosa (20.1%), Staphylococcus aureus (17.2%) and Escherichia coli (16.3%). Results for the third cultures showed persistence of P. aeruginosa (15.3%) and E. coli (14.2%). Gram-negative isolates dominated over Gram-positive ones (25.3% vs 15.1%, p < 0.05). Antibiotic sensitivity patterns before and after 1999 were: piperacillin-tazobactam 74% vs 66% (p < 0.005), imipenem 77% vs 85% (NS), cefoperazone-sulbactam 47% vs 44% (p < 0.005), amikacin 62% vs 78% (NS), ceftriaxone 41% vs 36% (p < 0.005), amoxicillin-clavulanate 51% vs 43% (p < 0.05) and clindamycin 43% vs 36% (p < 0.005), respectively.
Unlike in the West, in India Gram-negative bacteria were found to have always been dominant in the wounds of patients with diabetic foot infections. Infection with polymicrobial multidrug-resistant Gram-negative bacilli is common. The policy of empirical antimicrobial therapy at tertiary care needs to be changed.
Diabetologia 01/2011; 54(1):58-64. · 6.81 Impact Factor
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ABSTRACT: To analyze host genetic factors immunoglobulin G Fc receptors (FcgammaRs) and human leukocyte antigen (HLA) class II in GBS patients.
FcgammaRIIA, IIIA and IIIB polymorphisms were studied in 80 each GBS patients and healthy controls by allele specific PCR. HLA class II DRbeta1 and DQbeta1 typing was performed at the two-digit level by PCR in randomly selected 54 GBS patients and 202 controls.
FcgammaRIIA-H/H (56% vs 9%; P < 0.0001) and FcgammaRIIIA-V/V (40% vs 13%; P < 0.0001) genotypes, H131 allele frequencies (0.73 vs 0.26, P < 0.0001) and HLA DQbeta1*060x (OR, 1.96; 95% CI, 1.26-3.04; P < 0.01) were significantly increased in GBS than controls. DRbeta1*0701 alone (OR, 10; 95% CI, 45.90-2.25; P < 0.001) and together with FcgammaRIIA-H/H (OR, 11.03; 95% CI, 2.63-46.20; P < 0.001) was significantly associated with GBS patients having microbiological evidence of recent infection.
The study indicates that homozygous FcgammaRIIA and FcgammaRIIIA genotypes and FcgammaRIIA H131 allele are associated with GBS. HLA class II molecule DRbeta1*0701 is identified as novel genetic risk factor for development of GBS in patients with preceding infection.
Acta Neurologica Scandinavica 07/2010; 122(1):21-6. · 2.47 Impact Factor
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ABSTRACT: The combination of nonspecific clinical findings and similarities in morphologic appearances on imaging often makes it difficult to distinguish abscesses from other brain lesions. We present a retrospective analysis of in vivo (1)H-MR spectroscopy data for characterization of the etiology of the brain abscess based on the established criteria and demonstrate the sensitivity and specificity of metabolite markers assigned to specific bacterial groups defined by the microbial culture in 194 patients.
Conventional MR imaging and in vivo (1)H-MR spectroscopy data were evaluated from patients with pyogenic brain abscesses, with ages ranging from 3 to 60 years. Imaging and (1)H-MR spectroscopy were performed on a 1.5T scanner. After MR imaging was performed and analyzed, pus aspirates were obtained in all patients. The causative organisms were confirmed by pus cultures.
Resonance of AAs with or without other metabolites on in vivo (1)H-MR spectroscopy was observed in 80% of abscesses, with a sensitivity and specificity of 0.72 and 0.30, respectively. Most obligate anaerobes and some facultative anaerobes showed the presence of Lac/Lip, AAs, and Ac with or without Suc. Mostly obligate aerobes or facultative anaerobes showed the presence of Lac and AAs, with or without lipids.
The presence of AAs on in vivo (1)H-MR spectroscopy is a sensitive marker of pyogenic abscess, but its absence does not rule out a pyogenic etiology. The presence of Ac with or without Suc favors an anaerobic bacterial origin of the abscess; however, this may also be seen in some of the abscesses secondary to facultative anaerobes.
American Journal of Neuroradiology 10/2009; 31(2):360-6. · 2.93 Impact Factor
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ABSTRACT: Aeromonas caviae strains have been isolated from blood and stool cultures of three immunocompetent patients, residents of Northern India, who presented with community acquired septicemia without any recent history of diarrhea. Cell culture infectivity test performed on Hep-2 cells have shown substantial degree of invasiveness in the isolated strains. This case unleashes a possibility of asymptomatic gastrointestinal carriage of such strains of A. caviae in a very large population of India, as several areas of India have very high rates of Aeromonas induced acute diarrhea/gastroenteritis (up to 13%). It needs to be appraised further in India as well as other countries having high rates of Aeromonas induced acute diarrhea/gastroenteritis.
The Brazilian journal of infectious diseases: an official publication of the Brazilian Society of Infectious Diseases 01/2009; 12(6):547-8. · 0.55 Impact Factor
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R K Gupta,
K Nath,
A Prasad, K N Prasad,
M Husain,
R K S Rathore,
N Husain,
C Srivastava,
P Khetan,
R Trivedi,
P A Narayana
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ABSTRACT: Neuroinflammatory molecules, including tumor necrosis factor-alpha, interleukin1-beta, lymphocyte function associated molecule-1, and intercellular cell adhesion molecule-1 contribute to the development of brain abscess. We hypothesized that the high fractional anisotropy (FA) in the brain abscess cavity reflects the upregulation of these neuroinflammatory molecules. Materials and
Diffusion tensor imaging (DTI) was performed in 24 patients with brain abscess and Staphylococcus aureus-treated as well as nontreated Jurket cell lines (at 4 time points: 1, 24, 48, and 72 hours). Neuroinflammatory molecules were quantified from the brain abscess cavity aspirate of the patients as well as from the heat-killed S aureus-treated and nontreated cell lines and correlated with DTI measures.
The DTI-derived FA strongly correlated with the presence of neuroinflammatory molecules in the pus as well as in S aureus-treated cell lines; no such correlation was observed in nontreated cell lines.
These data indicate that neuroinflammatory molecules confer high diffusion anisotropy inside the brain abscess cavity. We propose that increased FA reflects upregulated inflammatory response in brain abscess.
American Journal of Neuroradiology 03/2008; 29(2):326-32. · 2.93 Impact Factor
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ABSTRACT: It is difficult to differentiate the cause of brain abscesses with the use of CT and MR imaging. We did a comparative evaluation of pyogenic, tubercular, and fungal brain abscesses by using conventional, diffusion-weighted imaging (DWI), and proton MR spectroscopy (PMRS) with an aim to define the unique features that may differentiate among the pyogenic, tubercular, and fungal brain abscesses.
We performed a retrospective analysis on 110 patients with surgically proved brain abscesses. Imaging studies included T2, T1, postcontrast T1, DWI, and PMRS. Apparent diffusion coefficient (ADC) of the wall and cavity of the abscesses were quantified. The morphologic, physiologic, and metabolite features of pyogenic (n=91), tubercular (n=11), and fungal (n=8) abscesses were compared.
The pyogenic abscesses had smooth (55/91) and lobulated (36/91) walls, whereas the tubercular abscesses had smooth (4/11), lobulated (6/11), or crenated walls (1/11) with no intracavitary projections. The fungal abscesses showed irregular walls (lobulated 4/8, crenated 4/8) with intracavitary projections (8/8). The wall as well as the cavity showed low ADC in the pyogenic and tubercular abscesses. In the fungal abscesses, the wall and projections showed low ADC (8/8); however, the cavity itself showed high ADC (8/8). PMRS showed cytosolic amino acids (89/91), acetate (25/91), and succinate (18/91) in the pyogenic abscesses, whereas lipid/lactate (11/11) was seen in the tubercular abscesses. The fungal abscesses showed lipid (4/8), lactate (7/8), amino acids (4/8), and multiple peaks between 3.6 and 3.8 ppm assigned to trehalose (5/8).
Based on the morphologic, ADC, and metabolite information, it may be possible to differentiate among the pyogenic, tubercular, and fungal brain abscesses.
American Journal of Neuroradiology 09/2007; 28(7):1332-8. · 2.93 Impact Factor
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ABSTRACT: Preceding infections and anti-ganglioside antibodies were assessed among 80 Guillain-Barré syndrome (GBS) patients and 125 controls. Previous infections were more frequent among GBS patients than among controls (p <0.0001), and had a significant association with axonal subtype compared with acute inflammatory demyelinating polyneuropathy (AIDP) (29/46 vs. 10/34 patients; p <0.05). Campylobacter jejuni (26%) was the most common preceding infection among GBS patients, followed by Mycoplasma pneumoniae (15%). Anti-ganglioside antibodies were detected more frequently among GBS patients than among controls (65/80 vs. 13/125; p <0.001), and a higher proportion of axonal cases had these antibodies than did AIDP patients (43/46 vs. 22/34; p <0.01).
Clinical Microbiology and Infection 03/2007; 13(3):334-7. · 4.54 Impact Factor
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ABSTRACT: Subacute sclerosing panencephalitis (SSPE), a rare progressive degenerative disease, is caused by persistent infection with a defective measles virus. The correlation between the clinical staging and MR imaging is usually poor. The aim of the study was to investigate the role of diffusion tensor imaging (DTI) in the early detection of white matter damage in SSPE in the presence of normal findings on conventional imaging.
DTI was performed in 21 patients in stage II SSPE and 10 age/sex-matched healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated in the periventricular white matter, corpus callosum, and posterior limb of the internal capsule in patients with normal and abnormal findings on conventional imaging as well as healthy controls.
The patients were grouped into those with normal (n = 11) and abnormal (n = 10) findings on conventional imaging for the purpose of quantitative DTI analysis. Abnormal- and normal-appearing white matter on T2-weighted images showed significantly decreased FA values in all the regions compared with those in healthy controls. MD values were significantly increased in the periventricular white matter region of the frontal and parietooccipital lobe in patients with normal as well as abnormal findings on conventional imaging compared with those in healthy controls.
DTI detects early white matter abnormalities that may have significant therapeutic implication, even in the presence of normal findings on conventional imaging, in patients with SSPE.
American Journal of Neuroradiology 10/2006; 27(8):1712-6. · 2.93 Impact Factor
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ABSTRACT: Polymicrogyria (PMG), a neuronal migration disorder, commonly manifests as a seizure disorder. The aim of this study was to look for the abnormalities in the underlying white matter using diffusion tensor imaging (DTI) that appeared normal on conventional magnetic resonance imaging (MRI) in patients with PMG.
DTI was performed in three patients with PMG and eight age- and sex-matched healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated for the cortex and adjoining subcortical white matter in both controls and patients.
We observed a significantly decreased mean FA value with no significant change in the MD value in subcortical white matter underlying polymicrogyric cortex (FA = 0.23+/-0.04, MD = 1.0+/-0.05 x 10(-3) mm(2)/s) as compared to both contralateral (FA = 0.32+/-0.04, MD = 1.0+/-0.05 x 10(-3) mm(2)/s) and normal control (FA = 0.32+/-0.04, MD = 1.0+/-0.06 x 10(-3) mm(2)/s) white matter. Significantly increased MD and decreased FA values were also observed in the polymicrogyric cortex (FA = 0.08+/-0.01, MD = 1.2+/-0.10 x 10(-3) mm(2)/s) as compared to normal contralateral (FA = 0.12+/-0.04, MD = 1.1+/-0.09 x 10(-3) mm(2)/s) and normal control (FA = 0.12+/-0.01, MD = 1.1+/-0.09 x 10(-3) mm(2)/s) cortex.
Significantly decreased FA values with no change in MD values in the subcortical white matter subjacent to polymicrogyric cortex reflect microstructural changes in the white matter probably due to the presence of ectopic neurons.
Neuroradiology 07/2006; 48(6):422-7. · 2.82 Impact Factor
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ABSTRACT: Nosocomial pneumonia is a common complication in mechanically ventilated patients. A study was carried out to determine the incidence, common bacterial etiologic agents and their antimicrobial susceptibility, and outcome of such pneumonia in an Intensive Care Unit (ICU) of a tertiary care center. In Surgical ICU (SICU) 176 patients required mechanical ventilation for more than 72 hours. A total of 39 (22.1%) of these patients developed nosocomial bacterial pneumonia as determined by microbiological assays. Endotracheal aspirate cultures detected a single bacterial isolate in 22 (56.4%) patients while two and three organisms were isolated from 10 (25.6%) and 7 (17.9%) patients respectively. Fifty three (84.1%) of a total of 63 isolates were Gram negative bacilli. The most frequently encountered pathogens were Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter species among the Gram negative bacilli and Staphylococcus aureus among the Gram positives. Resistance of bacterial isolates varied from 24 to 90% against commonly used antibiotics. Amikacin had the best profile, with 14% to 55% resistance against various isolates. Twenty three (59%) of 39 patients with pneumonia expired in the ICU. P. aeruginosa (25.6%) and K. pneunmoniae (17.9%) were the predominant isolates in these patients. Nosocomial pneumonia with high mortality is a frequent occurrence in mechanically ventilated patients in our ICU setting. Gram negative organisms with high levels of antimicrobial resistance are the most common isolates. Regular surveillance and monitoring of changes in antibiotic susceptibility of bacterial pathogens and appropriate therapeutic measures are likely to reduce the mortality in these patients.
The Journal of communicable diseases 01/2006; 37(4):281-7.
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ABSTRACT: The study was performed with the aim of prospectively characterizing infectious meningitis of different aetiology using magnetization transfer (MT) MRI. Spin-echo (SE) T(1), T(2) and pre- and post-contrast T(1) weighted MT images in 100 patients with aetiologically proven meningitis were evaluated for the visibility and enhancement of the meninges on pre- and post-contrast T(1) weighted MT images, respectively. The MT ratio (MTR) was calculated from the thickened meninges in tuberculous meningitis. In addition, the percentage difference in the mean signal intensity (SI) of the meninges and adjacent brain parenchyma was calculated and compared between different groups using 2-tailed student's t-test. T(1) weighted MT images were highly sensitive (96%) in the detection of abnormal meningeal enhancement. Meninges were visible on pre-contrast T(1) weighted MT images only in patients with tuberculous meningitis. The MTR from meninges in tuberculous infection was 19.10+/-1.02, and the percentage difference in the mean SI of the meninges and the adjacent T(2) normal brain parenchyma was significantly higher (p<0.05) in the tuberculous group compared with that in the non-tuberculous group. MT MRI is an important technique for the detection and characterization of infectious meningitis of different aetiology. Visibility of the meninges on pre-contrast T(1) weighted MT images may be considered highly suggestive of tuberculous meningitis.
British Journal of Radiology 06/2004; 77(917):387-94. · 1.31 Impact Factor
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ABSTRACT: Fungal peritonitis (FP) is a serious complication in patients on continuous ambulatory peritoneal dialysis (CAPD). We reviewed our FP cases to analyse the causative agents and possible risk factors in relation to FP and its outcome and mortality.
Records of all FP cases were reviewed. FP was diagnosed based on effluent cell count and positive fungal culture in suitable media.
Between October 1993 and November 2001, 261 patients underwent CAPD. FP was detected in 28 patients, one episode in each patient (14.3% of the total peritonitis episodes). Candida species and dematiaceous fungi+/-Candida species were responsible for 89.3 and 10.7% of episodes, respectively. Patients with preceding bacterial peritonitis (BP) developed FP more frequently (25.6%) than de novo cases (2.9%) (P<0.0001) and lower proportion of them continued CAPD (8.6% vs. 60%; P=0.007). Mortality in patients having abdominal pain with and without fever, and catheter in situ was significantly higher than in those patients who did not have these risk factors (9/11 vs. 6/17, P=0.01; 13/17 vs. 2/11, P=0.003; 6/6, vs. 9/22, P=0.01, respectively).
Higher proportion of our patients had FP; preceding BP was a significant risk factor for development of FP and technique failure. Abdominal pain+/-fever in patients and catheter in situ were identified as risk factors associated with mortality.
Journal of Infection 01/2004; 48(1):96-101. · 4.13 Impact Factor
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ABSTRACT: A retrospective analysis of 326 clinically diagnosed cases with meningitis over a period of five-and-a-half years was carried out to determine the prevalence of cryptococcal infection, its associated risk factors and therapeutic outcome. Fifty-four (16.6%) patients with cryptococcal meningitis were identified by smear examination, culture and/or cryptococcal antigen latex agglutination test. Records of 45 cryptococcal meningitis patients were available; 18 (40%) of them were apparently healthy immunocompetent individuals, 13 (28.9%) had human immunodeficiency virus (HIV) infection, 9 (20%) were renal transplant recipients, 4 (8.9%) were diabetic and 1 (2.2%) had systemic lupus erythematosus. Ten (22.2%) patients died and 11 (24.4%) patients (all HIV-positive) left against medical advice. The present study indicates that cryptococcal infection is associated with high mortality. Presenting symptoms being indistinguishable from other causes of central nervous system infection, all patients with a clinical diagnosis of meningitis, irrespective of their immune status should be investigated for cryptococcal infection.
Neurology India 10/2003; 51(3):364-6. · 0.96 Impact Factor
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ABSTRACT: Abscess formation is a common bacterial infection and requires an immediate antimicrobial approach for apposite treatment. Delay in patient treatment is usually a common feature, as the bacterial identification of clinical samples is based on the culture, which is a time-consuming exercise. The current study was aimed at developing an alternative technique with the potential for rapid bacterial group identification.
In the present study we performed ex vivo proton magnetic resonance spectroscopy of 40 pus samples collected from abscesses in different locations and the results have been retrospectively compared with the microorganism identified in the pus culture. In addition, the microbes obtained from the culture have been further subcultured and studied with magnetic resonance spectroscopy to identify the bacterial fingerprint in the pus sample seen on spectroscopy.
On reviewing the spectra obtained from the various abscesses, they were found to be qualitatively similar for a particular bacterium. The similar spectral pattern of the pus with obligate aerobes/anaerobes and pure cultures of the same bacteria suggests its strict metabolism under in vivo and in vitro conditions, respectively.
The characteristic metabolite pattern of obligate anaerobes may be used as a prototype for its rapid identification. This information may be of value for more appropriate clinical management of such cases.
European Journal of Clinical Investigation 07/2003; 33(6):518-24. · 3.02 Impact Factor
