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Savitri Sharma

Publications and source records attributed to Savitri Sharma.

At least 37 records · Page 2Linked to original sources
PubMed2004

Applicability of rapid antibiotic susceptibility testing in the management of bacterial endophthalmitis.

PURPOSE: To compare the applicability of the Kirby-Bauer disk diffusion method (conventional method) and the rapid antibiotic susceptibility test (RAST) for susceptibility testing of bacteria in the management of bacterial endophthalmitis. METHODS: Vitreous samples from 114 consecutive patients with endophthalmitis who were seen between June 2002 and October 2002 were subjected to microbiological processing (smears and cultures for bacteria and fungi). Forty-seven of 114 samples could be tested by RAST. In addition, the bacterial isolates from 47 patients were tested for antibiotic susceptibility by the conventional method, and minimum inhibitory concentrations (MICs) of various antibiotics were determined. Clinical and microbiological data for these 47 patients were analyzed. RESULTS: Bacteria were isolated by routine culture from 18 (38.3%) of 47 samples; all 18 were tested by the conventional method, and MICs were determined for antibiotic susceptibility. Only 10 (55.6%) of these 18 samples were analyzed by RAST. Low inoculum and the slow-growing nature of the organisms (Streptococcus, 3; Staphylococcus epidermidis, 5) accounted for no growth on RAST plates in eight cases. Of four patients who were treated with repeated intraocular antibiotics, only one received RAST result-guided intraocular injection. Considering MIC testing as the gold standard, the sensitivity and specificity of RAST were either equal to (gentamicin, cefazolin, vancomycin, and chloramphenicol) or lower than (ciprofloxacin) those of the conventional technique. CONCLUSION: This comparative study failed to demonstrate a distinct advantage of RAST as a routine procedure in the management of bacterial endophthalmitis because of the need for trained staff to perform RAST, the nearly 50% negativity of culture, and the occasionally unreliable results.

Adolescent↗
PubMed2004

Clinical resistance of Staphylococcus keratitis to ciprofloxacin monotherapy.

PURPOSE: To review the in vitro susceptibility and the clinical response to 0.3% ciprofloxacin in Staphylococcus aureus keratitis. METHODS: This is a non-comparative case series derived from a prospectively collected database and analysed retrospectively. One hundred and twenty one patients presenting in the cornea service of LV Prasad Eye Institute, Hyderabad, India, between January 1993 and December 2000, and identified to have S. aureus keratitis were included in the study. All patients had received slitlamp evaluation of the cornea and diagnostic microbiologic workup. They were treated with topical antimicrobial therapy based on smear and culture results. All S. aureus isolates were tested for antibiotic susceptibility by disk diffusion and those resistant to ciprofloxacin were confirmed by testing for minimum inhibitory concentration. The patients' clinical response to the antimicrobial therapy was noted. RESULTS: Twenty-five (20.6%) of 121 isolates resistant to ciprofloxacin on in vitro susceptibility testing were further analysed in this study. Fifteen of these 25 (60%) patients were initially treated with topical ciprofloxacin. Twelve of 15 (80%) patients showed no clinical improvement (3-8 days). Based on antibiotic susceptibility results, the antibiotic therapy was modified to fortified cefazolin and gentamicin in seven (58.3%), to vancomycin in one and to chloramphenicol in four cases. The corneal infiltrate resolved in 11 (73.3%) of 15 cases. Two patients required penetrating keratoplasty (PK), one required evisceration, and one patient was lost to follow up. Nine of 25 patients were initially started on fortified cefazolin and gentamicin therapy based on smear positive for gram-positive cocci; this resulted in resolution of infiltrate in 44.4% (4/9) while three required change of antibiotics (vancomycin-2, chloramphenicol-1), one required PK and one patient was lost to follow up. One of 25 patients started and continued on chloramphenicol, showed no response and required PK. CONCLUSIONS: This study shows a significant resistance of S. aureus to many antibiotics including ciprofloxacin and highlights the need for an alternative to ciprofloxacin monotherapy for the treatment of staphylococcal keratitis.

Adolescent↗
PubMed2003

Clinico-microbiological correlation of suture-related graft infection following penetrating keratoplasty.

PURPOSE: To report the clinical and microbiological profiles of suture-related graft infections following penetrating keratoplasty. DESIGN: Interventional case series. METHODS: The medical and microbiology records of all patients who presented with suture-related graft infections and were seen between January 1999 and December 2001 were reviewed. RESULTS: Of 105 patients (105 eyes) who developed corneal infiltrates following penetrating keratoplasty, 37 patients (24 optical and 13 therapeutic) were identified as having suture-related graft infection. The median onset of infiltrates after penetrating keratoplasty was 87 days for 31 patients who presented within one year. Gram-stained smears of corneal scrapings were positive in 27 (73%) of 37 patients, whereas cultures were positive in 32 (only bacteria, 30; mixed bacteria and fungi, 2). Thirty-seven isolates were obtained from 32 patients (gram-positive bacteria, 32; gram-negative bacteria, 3; fungus, 2). All gram-positive isolates were sensitive to cefazolin, chloramphenicol, and vancomycin, whereas one of three gram-negative isolates (Pseudomanas species) was resistant to all the antibiotics tested. Of 32 patients, 30 (82%) responded satisfactorily to medical management. CONCLUSIONS: Suture-related graft infections are usually caused by bacteria that are sensitive to ciprofloxacin, cefazolin, and gentamicin, and the patients respond satisfactorily to medical therapy.

Adolescent↗
PubMed2003

Microsporidial keratoconjunctivitis in a HIV-seronegative patient treated with debridement and oral itraconazole.

PURPOSE: To report a case of microsporidial keratoconjunctivitis in an HIV-seronegative. METHODS: We report on a 40-year-old woman who presented with acute symptoms of 4 days' duration. Visual acuity was 6/6 in the right eye and 6/6 partial in the left eye. In the left eye, there was diffuse conjunctival congestion with papillary changes. There were multiple raised epithelial lesions in the cornea. RESULTS: Corneal scrapings stained with potassium hydroxide and calcofluor white showed Microsporidium spores in large numbers. These spores with polar staining were also confirmed in Gram stain. One month after initiation of itraconazole, the left eye was quiet. She had a visual acuity of 6/6 in that eye, with faint corneal haze. CONCLUSIONS: We report a rare case of microsporidial keratoconjunctivitis in a HIV-seronegative patient who was treated by debridement and oral itraconazole. Microsporidium should be suspected even in an immunocompetent individual if the corneal examination revealed showed multiple raised epithelial lesions.

Administration, Oral↗
PubMed2003

Trends in contact lens-associated microbial keratitis in Southern India.

OBJECTIVE: To review the microbiologic profile, clinical course, treatment, and outcome in patients with contact lens-associated microbial keratitis in the setting of a tertiary eye care center in a developing country in the Tropics. DESIGN: Retrospective noncomparative case series selected from an ongoing prospective series. PARTICIPANTS: Twenty-eight subjects examined in the contact lens clinic of L. V. Prasad Eye Institute, Hyderabad, south India, between February 1991 and September 2000, who presented with corneal stromal infiltrate on slit-lamp examination, were included in the study. INTERVENTION: All patients underwent standard diagnostic microbiologic evaluation and smear and culture-guided topical antimicrobial therapy. Penetrating keratoplasty was performed in some patients. MAIN OUTCOME MEASURES: Culture results and clinical response to antimicrobial therapy. RESULTS: Twenty eight (0.11%) of 23,889 contact lens-wearing patients presented with laboratory-proven infectious keratitis; this constituted 0.56% of 4967 corneal ulcer patients seen during the same period. Most (15/28) of the patients wore soft contact lenses on a daily basis. Rigid gas-permeable lenses were worn by six patients, therapeutic bandage contact lenses by four, and Silsoft lenses by four. Laboratory results showed bacterial infections in 25 patients (89.2%); Pseudomonas was the most common organism (13/25; 52%). Acanthamoeba, herpes simplex virus, and Aspergillus niger were isolated in one case each. Laboratory-based medical therapy led to the healing of ulcers in 24 (85.7%) of 28 patients, whereas 4 patients required penetrating keratoplasty. Most of the organisms were sensitive to antibiotics. CONCLUSIONS: Contact lens-associated microbial keratitis is rare in southern India. Soft contact lens wear is the most common risk factor; Pseudomonas keratitis is the predominant causative agent. Fungal, viral, and Acanthamoeba keratitis are rare. The offending bacteria are usually sensitive to antibiotics, and the treatment outcome with medical therapy is good.

Adolescent↗
PubMed2003

Decreased oxidative DNA damage and accelerated cell turnover in woodchuck hepatitis virus infected liver.

Infection of newborn woodchucks with woodchuck hepatitis virus (WHV) results in hepatocellular carcinoma (HCC). Since oxidative damage may be carcinogenic, we investigated the relationship between WHV infection and oxidative damage to hepatic lipids and DNA. Eastern woodchucks were infected with WHV. Hepatic lipid peroxidation was assessed in vitro in isolated hepatocytes by thiobarbituric acid reactive substances (TBARS). Oxidative DNA damage was assessed in vivo in snap-frozen livers by 8-hydroxy-2'-deoxyguanosine (8-OH-dG). The proliferation index (PI) and apoptotic index (AI) were also determined. WHV infection was associated with increased hepatic lipid peroxidation (0.51+/-0.04 nmols TBARS per mg protein for WHV+ hepatocytes vs. 0.38+/-0.04 for WHV negative controls, P<0.01). In contrast, the WHV+ livers exhibited less oxidative DNA damage than uninfected controls (11+/-5 vs. 38+/-8 8-OH-dG/10(6) dG, P<0.02). In WHV-infected animals PI and AI were increased, by >20-fold. We conclude that WHV infection is associated with increased in vitro lipid peroxidation and decreased in vivo oxidative DNA damage. The increased PI and AI in the WHV+livers suggest that rapid cell turnover dilutes 8-OH-dG concentration.

Journal Article↗
PubMed2003

Multiplex polymerase chain reaction for the detection of herpes simplex virus, varicella-zoster virus and cytomegalovirus in ocular specimens.

PURPOSE: A majority of ocular viral diseases are caused by herpes group of viruses. Such infections, especially atypical herpetic keratitis, iridocyclitis and intra-ocular inflammations, can often present with overlapping clinical manifestations misleading the diagnosis. Molecular techniques are most useful in such instances for an accurate and rapid diagnosis since conventional methods are time consuming and less sensitive. A multiplex PCR was developed and used for the detection of herpes simplex virus (HSV), varicella zoster virus (VZV), and cytomegalovirus (CMV) in ocular samples. METHODS: One hundred and forty six ocular samples (corneal scrapings - 52, aqueous fluid - 36, vitreous fluid - 31, tissues - 26, skin vesicle scraping - 1) were included in the study. The sensitivity of the assay was determined using serial dilutions of standard strains of HSV, VZV, and CMV vis-à-vis plaque forming assay. RESULTS: The sensitivity of the assay was 4, 4 and 12 PFU/ml or 20, 20 and 60 genome copy numbers of HSV, VZV and CMV respectively. Using DNA from various sources (fungal, bacterial, human leukocytes, tissues) along with standard positive controls, the assay was found to be highly specific. HSV DNA was detected in majority of the clinical samples (33.6%), most frequent being corneal samples. Comparatively, VZV and CMV infections were detected in small number of samples (VZV-3, CMV-2). CONCLUSIONS: We found the assay very useful in our set-up whenever a differential diagnosis of herpetic infections was suggested by the ophthalmologist. The multiplex PCR we have described here can be of greater value in clinics with larger number of patients suspected of having HSV, VZV or CMV infections.

Cytomegalovirus↗
PubMed2003

Current management strategies of acute post-operative endophthalmitis.

The current management of acute post-operative endophthalmitis relies on microbial confirmation, intravitreal antibiotics, and vitrectomy. The endophthalmitis vitrectomy study (EVS) demonstrated that systemic antibiotics are not necessary in post-cataract/secondary intraocular lens (IOL) acute bacterial endophthalmitis, and that vitrectomy could be required only for eyes with presenting vision of light perception. Since the publication of the EVS newer tests are available for microbial confirmation, and many new and effective antibiotics are discovered for systemic therapy. We have studied large numbers of patients with endophthalmitis over several years. Perhaps our experience represents the endophthalmitis status in the developing countries. The article is a synthesis of recent publications in the world literature. Finally the authors have suggested a management strategy for acute post-cataract acute bacterial endophthalmitis.

Acute Disease↗
PubMed2003

Clinical characterization of corneal infiltrative events observed with soft contact lens wear.

PURPOSE: Corneal infiltrates are commonly observed during adverse reactions associated with contact lens wear. Broad ranges of presentations are encountered, and there is no well-established classification system. The aim of this paper is to categorize corneal infiltrates associated with soft lens wear and present the typical clinical characteristics associated with each type of event. METHODS: All events of corneal infiltrates occurring in soft contact lens clinical trials over 10 years (9 years retrospective and 1 year prospective) and conducted at two contact lens research centers were reviewed by a panel of experts comprising ophthalmologists, optometrists, and other biologic scientists. Classification of each event was based on assessment of a range of signs and symptoms by the review panel. RESULTS: A classification scheme was devised to distinguish infiltrative events that were serious and symptomatic (microbial keratitis), clinically significant and symptomatic (contact lens-induced peripheral ulcer, contact lens-induced acute red eye, infiltrative keratitis), and clinically nonsignificant and asymptomatic (asymptomatic infiltrative keratitis and asymptomatic infiltrates). CONCLUSION: Corneal infiltrates can be classified into six distinct categories. This classification scheme, based on clinical characteristics, should aid diagnosis, management, and treatment of corneal infiltrates as well as assisting investigations into the etiology of each of these conditions.

Contact Lenses, Hydrophilic↗
PubMed2003

Plasma markers of platelet activation in cystic fibrosis liver and lung disease.

BACKGROUND: Transforming growth factor beta 1 (TGFbeta1) is a major fibrogenic cytokine, the expression of which is increased in the livers of children with cystic fibrosis liver disease (CFLD) and in the bronchoalveolar lavage fluid of patients with cystic fibrosis pulmonary disease (CFPD). The purpose of our study was to investigate the usefulness of plasma TGFbeta1 as a noninvasive marker of CFLD and CFPD, or both and to investigate the contribution of platelet-derived TGFbeta1 to plasma TGFbeta1 by correlating the latter with platelet factor 4 (PF4). METHODS: Three groups of patients with cystic fibrosis were studied: 1) those with CFLD, 2) those with CF and no liver disease (CFNLD), and 3) those with CFPD. Controls were healthy adolescents and adults. Plasma TGFbeta1 was assayed using the R and D Quantikine quantitative sandwich enzyme immunoassay technique and PF4 (American Bioproducts ELISA kit). RESULTS: Plasma TGFbeta1 was markedly increased in CFPD (15 +/- 3 ng/mL) versus healthy adults (1 +/- 0 ng/mL; P < 0.004. The PF4 values followed a similar pattern: 105 +/- 8 ng/mL in CFPD versus 12 +/- 4 ng/mL (P < 0.0001). Plasma TGFbeta1 values in CFLD did not differ from CFNLD patients of comparable age nor from values for healthy adolescents. Plasma TGFbeta1 values were strongly correlated with values for PF4: r = 0.543, P < 0.0001. CONCLUSIONS: Plasma TGFbeta1 is not a useful marker of CFLD. The increased plasma TGFbeta1 and PF4 in CFPD patients are of interest both as possible noninvasive markers of pulmonary fibrosis and because the increased values suggest that platelet activation may play a pathogenetic role in CFPD.

Adult↗
PubMed2003

Use of 18S rRNA gene-based PCR assay for diagnosis of acanthamoeba keratitis in non-contact lens wearers in India.

Identification of Acanthamoeba cysts and trophozoites in ocular tissues requires considerable expertise and is often time-consuming. An 18S rRNA gene-based PCR test, highly specific for the genus Acanthamoeba, has recently been reported in the molecular diagnosis of Acanthamoeba keratitis. This PCR assay was compared with conventional microbiological tests for the diagnosis of Acanthamoeba keratitis. In a pilot study, the PCR conditions with modifications were first tested on corneal scrapings from patients with culture-proven non-contact lens-related Acanthamoeba, bacterial, and fungal keratitis. This was followed by testing of corneal scrapings from 53 consecutive cases of microbial keratitis to determine sensitivity, specificity, and predictive values of the assay. All corneal scrapings from patients with proven Acanthamoeba keratitis showed a 463-bp amplicon, while no amplicon was obtained from patients with bacterial or fungal keratitis. Some of these amplified products were sequenced and compared with EMBL database reference sequences to validate these to be of Acanthamoeba origin. Out of 53 consecutive cases of microbial keratitis included for evaluating the PCR, 10 (18.9%) cases were diagnosed as Acanthamoeba keratitis on the basis of combined results of culture, smear, and PCR of corneal scrapings. Based on culture results as the "gold standard," the sensitivity of PCR was the same as that of the smear (87.5%); however, the specificity and the positive and negative predictive values of PCR were marginally higher than the smear examination (97.8 versus 95.6%, 87.5 versus 77.8%, and 97.8 versus 97.7%) although the difference was not significant. This study confirms the efficacy of the PCR assay and is the first study to evaluate a PCR-based assay against conventional methods of diagnosis in a clinical setting.

Acanthamoeba↗
PubMed2003

Advantages of using mitochondrial 16S rDNA sequences to classify clinical isolates of Acanthamoeba.

PURPOSE: This work was intended to test the classification of Acanthamoeba into genotypes based on nuclear ribosomal RNA gene (18S rDNA, Rns) sequences. Nearly all Acanthamoeba keratitis (AK) isolates are genotype RnsT4. This marked phylogenetic localization is presumably either due to an innate potential for pathogenicity or to a peculiarity of the gene sequences used. To differentiate between these possibilities, relationships among isolates have been reexamined, using a second gene. METHODS: Phylogenetic relationships among isolates of Acanthamoeba were studied, using sequences of the mitochondrial small subunit ribosomal RNA gene (16S rDNA; rns). Genotypes based on complete sequences of approximately 1540 bp were determined for 68 strains, by using multiple phylogenetic analyses. RESULTS: Each strain's mitochondria contained a single intron-free rns sequence (allele). The 68 strains had 35 different sequences. Twenty-eight strains had unique sequences, and 40 strains each shared one of the seven remaining sequences. Eleven mitochondrial rns genotypes corresponding to 11 of 12 previously described nuclear Rns genotypes were identified. Genotype rnsT4 was subdivided into eight distinct clades, with seven including Acanthamoeba keratitis (AK) isolates. CONCLUSIONS: The phylogenetic clustering of AK isolates was confirmed and thus is not specific to the nuclear gene. Rns and rns sequences are both suitable for genotyping of ACANTHAMOEBA: However, the mitochondrial sequences are shorter and more consistent in length, have a higher percentage of alignable bases for sequence comparisons, and have none of the complications caused by multiple alleles or introns, which are occasionally found in Rns. In addition, the more common occurrence of strains with identical rns sequences simplifies identification and clustering of isolates.

Acanthamoeba↗
PubMed2002

Reliability of nested polymerase chain reaction in the diagnosis of bacterial endophthalmitis.

PURPOSE: To test the utility of DNA Taq polymerase (Taq) treated with 8-methoxypsoralen with ultraviolet irradiation and Taq treated with restriction endonuclease in a nested polymerase chain reaction test for the diagnosis of bacterial endophthalmitis. METHODS: Prospective, comparative study. Vitreous biopsy fluid from 32 cases of clinically diagnosed bacterial endophthalmitis and 10 noninfective controls were cultured for aerobic/anaerobic bacteria and tested by nested polymerase chain reaction using two sets of universal eubacterial primers in triplicate with untreated Taq, Taq treated with 8-methoxypsoralen with ultraviolet irradiation, and Taq treated with Sau 3A1. RESULTS: Using untreated Taq, false-positive results were obtained in nested polymerase chain reaction with all 10 control samples, which were not seen with the other two methods of nested polymerase chain reaction. However, the sensitivity of nested polymerase chain reaction using Sau 3A1 was the same sensitivity as the conventional culture (34.4%), whereas the sensitivity of the nested polymerase chain reaction using 8-methoxypsoralen was 46.9% higher than in the conventional culture. CONCLUSION: To eliminate the problem of false positives in bacterial nested polymerase chain reaction, we recommend the routine utilization of Taq treated with 8- methoxypsoralen and ultraviolet irradiation.

Bacteria↗
PubMed2002

Effect of vancomycin on Staphylococcus epidermidis adherence to poly(methyl methacrylate) intraocular lenses.

PURPOSE: To study the adherence of Staphylococcus epidermidis in variable loads (10(8) cfu/mL and 10(3) cfu/mL) to poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) and to evaluate the effect of vancomycin treatment on S epidermidis adherence to the IOL. SETTING: L.V. Prasad Eye Institute, Hyderabad, India. METHODS: The study was designed in 2 parts. Phase I: Twelve PMMA IOLs were soaked in a solution of S epidermidis, randomized to 10(8) cfu/mL or 10(3) cfu/mL. They were rinsed or rinsed and vortexed and cultured. Phase II: Twelve IOLs were treated with vancomycin (10 mg/mL), randomized to before and after treatment with S epidermidis. RESULTS: Staphylococcus epidermidis adhered to all portions of the IOL with 10(8) cfu/mL and 10(3) cfu/mL bacterial loads. Treatment with vancomycin reduced S epidermidis adherence. CONCLUSION: Pretreatment of an IOL with vancomycin or a suitable antibiotic agent appears to reduce bacterial adherence to the IOL. Placement of a sustained-release device that could release an antibiotic agent over a specific period, reducing the incidence of postcataract endophthalmitis, should be studied.

Anti-Bacterial Agents↗
PubMed2002

The epidemiological features and laboratory results of fungal keratitis: a 10-year review at a referral eye care center in South India.

PURPOSE: To report the epidemiological features and laboratory results of 1,352 cases of fungal keratitis diagnosed at the L.V. Prasad Eye Institute (LVPEI) in south India. METHODS: The medical and microbiology records of 1,352 culture proven cases (1,354 eyes) of fungal keratitis diagnosed at the LVPEI between January 1991 to December 2000 was retrospectively reviewed for demographic features, risk factors, seasonal variation, and laboratory findings. RESULTS: Males (962) were affected significantly more (p< 0.0001) than females (390). Of 1,352 patients, 853 (64.4%) were in the younger age group (16-49 years). Ocular trauma predisposed to infection in 736 (54.4%) of 1,354 eyes. There was a higher incidence of fungal keratitis during the monsoon and winter than summer. A fungal cause was established by smears of corneal scrapings in 1,277 (95.4%) eyes. The potassium hydroxide preparation (KOH), Calcofluor white (CFW), Gram-, and Giemsa-stained smears revealed fungus in 1,219 (91.0%), 1,224 (91.4%), 1,181 (88.2%), and 1,139 (85.1%) eyes, respectively. Fusarium(506, 37.2%) and Aspergillus species (417, 30.7%) predominated the hyaline fungal spectrum (1,133) and Curvularia species (39, 2.8%) were the highest among the dematiaceous isolates (218). CONCLUSIONS: To the best of our knowledge, this review presents the epidemiological features and laboratory results of the largest series of fungal keratitis ever reported in the literature. Keratomycosis is predominant in young adults with trauma as the major predisposing factor. With fungal keratitis being a major ophthalmologic problem in the tropical regions of the world, data available on the epidemiological features of a large series would greatly help medical practitioners at primary and secondary health care centers in the management of the disease. A simple KOH preparation of corneal scraping alone is highly beneficial in confirming the diagnosis.

Adolescent↗
PubMed2002

Evaluation of corneal scraping smear examination methods in the diagnosis of bacterial and fungal keratitis: a survey of eight years of laboratory experience.

PURPOSE: To determine the sensitivity, specificity, and predictive values of Gram and potassium hydroxide with calcofluor white (KOH+CFW) stains in the diagnosis of early and advanced microbial keratitis, a retrospective analysis of comparative data from a prospectively collected database was done. METHODS: Patients with nonviral microbial keratitis seen at L.V. Prasad Eye Institute between February 1991 and December 1998 were included in the study. The type of bacteria seen on Gram stain was determined from 251 corneal scrapings from patients with early keratitis and 841 corneal scrapings from patients with advanced keratitis. The presence of fungi in corneal scrapings was determined by KOH+CFW stain of 114 and 363 scrapings from patients with early and advanced keratitis, respectively. The smear findings were compared with culture results to analyze specificity, sensitivity, and predictive values of the staining techniques. RESULTS: The sensitivity of Gram stain in the detection of bacteria was 36.0% in early and 40.9% in advanced keratitis cases; however, the specificity was higher in both groups (84.9% and 87.1%, respectively). Comparatively, the sensitivity and specificity of fungal detection were higher using KOH+CFW in early (61.1% and 99.0%, respectively) as well as advanced keratitis (87.7% and 83.7%, respectively). Predictive values were high for KOH+CFW in fungus detection, while they were poor for Gram stain in bacteria detection. In advanced keratitis cases, the false positives were higher in fungal detection (16.3%) than in bacterial detection (10.3%), while the false negatives were significantly higher in bacterial detection compared with fungal detection (59.1% versus 12.3%, p< 0.0001). In early keratitis, on the other hand, both false positives and false negatives for bacterial detection were significantly higher than fungal detection. CONCLUSIONS: Decisions can reliably be based on KOH+CFW stain of corneal scrapings for initiation of antifungal therapy in mycotic keratitis. The results of Gram stain, on the other hand, have limited value in therapeutic decisions for bacterial keratitis. Therefore, the search for a better modality for early and efficient diagnosis of bacterial keratitis needs to continue.

Cornea↗
PubMed2002

Anterior chamber tap: diagnostic and therapeutic indications in the management of ocular infections.

PURPOSE: To report three cases in which an anterior chamber tap was useful in the management of infection of the eye confined to the anterior segment. METHODS: In the first case, the patient presented with diffuse conjunctival congestion and thick anterior chamber exudates adhering to the back of the cornea. The second case involved fungal keratitis, and the patient was not responding to topical natamycin and systemic ketoconazole. In this patient, infiltrate and thick hypopyon persisted despite medical therapy. The patient in the third case had a persistent thick endothelial exudate, and a retained intracameral foreign body, fungal infection, and a cataract were suspected. In all three cases, an anterior chamber tap was performed. In case 1, the exudate was removed and sent for microbiologic investigation. In case 2, the hypopyon was evacuated and intracameral amphotericin B (5 microg) was injected. In case 3, the exudate contained a wooden foreign body that was sent for culture. Intracameral amphotericin B (5 microg) was injected. RESULTS: In the first case, the culture of the exudate grew Staphylococcus aureus. The eye quieted, and the exudate resolved following treatment with topical fortified cefazolin, fortified gentamicin, and systemic cefazolin. In the second case, smears of corneal scrapings revealed fungal filaments and the culture grew Aspergillus species. The infection resolved following an anterior chamber tap, but the patient developed a cataract. After cataract surgery, visual recovery was limited because of the corneal scar. In the third case, the culture of the foreign body grew an unidentified hyaline fungus. Following an anterior chamber tap, the infection resolved, but the cataract progressed. The patient did well after cataract surgery. CONCLUSIONS: An anterior chamber tap is an extremely useful procedure in the management of ocular infections confined to the anterior segment. The procedure should be performed under strict aseptic conditions. If the infection involves the anterior capsule of the lens, care should be taken to avoid injury to the lens, and the possibility of progression of the cataract should be explained to the patient.

Adult↗