Bartonella henselae infection in diverse clinical conditions in a tertiary care hospital in north India.

BACKGROUND & OBJECTIVES: : Bartonella henselae causes infections which closely resemble febrile illness and chronic diseases such as tuberculosis and haematological malignancies. There are not many studies on Bartonella infections from India. The present study was undertaken to diagnose B. henselae infection in diverse clinical conditions in a tertiary care hospital in north India. METHODS: A total of 145 patients including those with fever and lymphadenopathy, infective endocarditis and neuroretinitis were enrolled in the study. Whole blood, serum and lymph node aspirate and valvular vegetations if available, were obtained. Samples were plated on chocolate agar and brain-heart infusion agar containing five per cent fresh rabbit blood and were incubated at 35°C for at least four weeks in five per cent CO2with high humidity. Immunofluorescent antibody assay (IFA) was done for the detection of IgM antibodies in the serum using a commercial kit. Whole blood was used to perform polymerase chain reaction (PCR) for the citrate synthase gene (gltA). RESULTS: IFA was positive in 11 of 140 (7.85%) patients and PCR was positive in 3 of 140 (2.14%) patients. Culture was negative in all the cases. A higher incidence of Bartonella infection was seen in patients with fever and lymphadenopathy (n=30), seven of whom were children. In ophthalmological conditions, four cases were IFA positive. INTERPRETATION & CONCLUSIONS: The present study shows that the threat of Bartonella infection is a reality in India. It is also an important treatable cause of fever and lymphadenopathy in children. Serology and PCR are useful tests for its diagnosis. Clinicians should consider. BARTONELLA: infection in the differential diagnosis of febrile illnesses and chronic diseases.

BOLD fMRI and DTI in strabismic amblyopes following occlusion therapy.

Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) was sought in strabismic amblyopes. In this hospital-based case-control cross-sectional study, fMRI and DTI were conducted in strabismic amblyopes before initiation of any therapy and after visual recovery following the administration of occlusion therapy. FMRI was performed in 10 strabismic amblyopic subjects (baseline group) and in 5 left strabismic amblyopic children post-occlusion therapy after two-line visual improvement. Ten age-matched healthy children with right ocular dominance formed control group. Structural and functional MRI was carried out on 1.5T MR scanner. The visual task consisted of 8 Hz flickering checkerboard with red dot and occasional green dot. Blood-oxygen-level-dependent (BOLD) fMRI was analyzed using statistical parametric mapping and DTI on NordicIce (NordicNeuroLab) softwares. Reduced occipital activation was elicited when viewing with the amblyopic eye in amblyopes. An 'ipsilateral to viewing eye' pattern of calcarine BOLD activation was observed in controls and left amblyopes. Activation of cortical areas associated with visual processing differed in relation to the viewing eye. Following visual recovery on occlusion therapy, enhanced activity in bilateral hemispheres in striate as well as extrastriate regions when viewing with either eye was seen. Improvement in visual acuity following occlusion therapy correlates with hemodynamic activity in amblyopes.

Isolation & characterization of Bartonella sp. from optic neuritis patients.

BACKGROUND & OBJECTIVES: Optic neuritis (ON) is characterized by sudden and rapid impairment of vision. Bartonella henselae is a known aetiological agent of cat scratch disease (CSD), which is a common cause of neuroretinitis, the least common type of optic neuritis. The present study was carried out to determine the microbiological aetiology of optic neuritis in patients attending a tertiary care eye hospital in north India, which was later confirmed with molecular characterization. METHODS: Of the 50 patients suffering from optic neuritis reported to the Ophthalmology OPD of a tertiary care eye hospital in New Delhi, India, 29 were included in the study. Blood culture from these patients were processed for aerobic and anerobic cultures to rule out infective aetiology. Subsequently, PCR was done on archive, glycerol-stocked cultures. RESULTS: Gram-negative pleomorphic coccobacilli grew in four of 29 patients tested. Characterization of these revealed Bartonella like organism as tested by the API 20E, API Staph, API Strept and RapID ANA systems. Electron microscopy revealed presence of polar flagella and bleb like projection all over the bacterial surface. PCR performed on preserved culture confirmed these as Bartonella sp. INTERPRETATION & CONCLUSIONS: Infections with Bartonella like organisms have not been demonstrated from India in cases of optic neuritis or in any of the other clinical syndromes in the past. The present study shows the isolation and characterization of Bartonella like organisms from optic neuritis patients. From clinical point of view it will be important to look for these organisms as aetiological agents in ON cases in order to treat with appropriate antibiotics.

Comparative evaluation of megadose methylprednisolone with dexamethasone for treatment of primary typical optic neuritis.

AIM: To compare the efficacy of intravenous methylprednisolone and intravenous dexamethasone on visual recovery and evaluate their side-effects for the treatment of optic neuritis. MATERIALS AND METHODS: Prospective, randomized case-controlled study including 21 patients of acute optic neuritis presenting within eight days of onset and with visual acuity less then 20/60 in the affected eye who were randomly divided into two groups. Group I received intravenous dexamethasone 200 mg once daily for three days and Group II received intravenous methylprednisolone 250 mg/six-hourly for three days followed by oral prednisolone for 11 days. Parameters tested were pupillary reactions, visual acuity, fundus findings, color vision, contrast sensitivity, Goldmann visual fields and biochemical investigations for all patients at presentation and follow-up. RESULTS: Both groups were age and sex-matched. LOGMAR visual acuity at presentation was 1.10 +/- 0.52 in Group I and 1.52 +/- 0.43 in Group II. On day 90 of steroid therapy, visual acuity improved to 0.28 +/- 0.33 in Group I and 0.36 +/- 0.41 in Group II ( P =0.59). At three months there was no statistically significant difference in the color vision, contrast sensitivity, stereoacuity, Goldman fields and the amplitude and latency of visually evoked response between the two groups. The concentration of vitamin C, glucose, sodium, potassium, urea and creatinine were within the reported normal limits. CONCLUSION: Intravenous dexamethasone is an effective treatment for optic neuritis. However, larger studies are required to establish it as a safe, inexpensive and effective modality for the treatment of optic neuritis.

Incidence and progression of myopia and associated factors in urban school children in Delhi: The North India Myopia Study (NIM Study).

AIM: To evaluate the incidence and progression of myopia and factors associated with progression of myopia in school going children in Delhi. METHODS: Prospective longitudinal study of 10,000 school children aged 5 to 15 years screened after an interval of 1 year to identify new myopes (Spherical Equivalent≤ -0.5D) and progression of myopia in previously diagnosed myopic children. Association between risk factors and progression was analyzed using adjusted odds ratio. RESULTS: Of the 9,616 children re-screened (97.3% coverage), annual incidence of myopia was 3.4%with mean dioptric change of -1.09 ± 0.55. There was a significant higher incidence of myopia in younger children compared to older children (P = 0.012) and among girls compared to boys (P = 0.002). Progression was observed in 49.2%children with mean dioptric change of -0.27 ± 0.42 diopters. The demographic and behavioral risk factors were analyzed for children with progression (n = 629) and adjusted odds ratio values were estimated. Hours of reading-writing/week (p<0.001), use of computers/ video games (P<0.001) and watching television (P = 0.048) were significant risk factors for progression of myopia. Outdoor activities / time spent outdoors> 2 hours in a day were protective with an inverse association with progression of myopia (P< 0.001). CONCLUSION: Myopia is an important health issue in India and is associated with long hours of reading and screen time with use of computers and video games. An annual eye vision screening should be conducted, and outdoor activities be promoted to prevent the increase of myopia among school children.

A prospective clinical evaluation of augmented Anderson procedure for idiopathic infantile nystagmus.

PURPOSE: To evaluate the efficacy of the augmented Anderson procedure in idiopathic infantile nystagmus (IIN). METHODS: Twelve consecutive patients older than 5 years having IIN with eccentric null position and anomalous head position were enrolled in an institution-based study. Best-corrected visual acuity (uniocular and binocular and in both null position and primary position), slit-lamp examination, fundus examination, ocular motility examination, and stereopsis using TNO were recorded. In all cases the augmented Anderson procedure, that is, recession of the yoke muscles (9-mm medial rectus and 12-mm lateral rectus), was performed. Eye movements were recorded before and 3 months after surgery in the primary position, right gaze 15 and 30 degrees, and left gaze 15 and 30 degrees. RESULTS: All patients had improvement in their anomalous head posture after surgery (p = 0.0001). The nystagmus intensity in the primary position decreased from 22.0 +/- 15.9 degrees cycles/s preoperatively to 10.6 +/- 10.2 degrees cycles/s at 3 months postoperatively. The change was statistically significant (p = 0.006). After surgery, binocular visual acuity using the Early Treatment Diabetic Retinopathy Study chart improved in primary position (p = 0.007). No patient developed more than mild limitation of horizontal movements after surgery. CONCLUSION: The augmented Anderson procedure is successful in correcting face turn in patients having IIN with eccentric null position, resulting in an increase in visual acuity and a decrease in nystagmus intensity in primary position. Further studies with a longer follow-up are required to assess the long-term efficacy of this procedure.

Cone-rod dystrophy and acquired dissociated vertical nystagmus.

Although usually a manifestation of vestibular or neurological disease, acquired nystagmus occasionally can be seen in ocular diseases such as ocular albinism and cone dystrophy. The present case of cone-rod dystrophy presenting with acquired dissociated vertical nystagmus probably demonstrates another unusual manifestation of cone-rod dystrophy.

Effect of posterior tenectomy of the superior oblique on objective and subjective torsion in cases of superior oblique overaction.

PURPOSE: To evaluate the effect of posterior tenectomy of the superior oblique on the correction of A-pattern, superior oblique overaction and the changes in torsion that occur in such cases. PATIENTS AND METHODS: This prospective study included 15 consecutive cases of bilateral superior oblique overaction with an A-pattern of more than 20 PD, a difference of deviation between 25 degrees up-gaze and 35 degrees downgaze, and superior oblique overaction of 2+ to 3+ on a scale of 0 to 4+. Deviation was measured in the primary position, 25 degrees upgaze, and 35 degrees downgaze using the prism bar cover test, and torsion was measured using a synoptophore, the double Maddox rod test, and fundus photographs. Measurements were obtained preoperatively and postoperatively at 1 week, 1 month, and 3 months. All case-patients underwent a standard temporal route posterior tenectomy of the superior oblique by a single surgeon. RESULTS: Mean age was 11.2 +/- 4.2 years with 14 cases of A-pattern exotropia. Mean superior oblique overaction was 2.60 +/- 0.50 in the right eye and 2.26 +/- 0.45 in the left eye, which decreased postoperatively to 2.20 +/- 0.56 and 1.80 +/- 0.41, respectively. The index of surgical effect was 0.84 in the right eye and 0.79 in the left eye. Postoperatively, mean correction of the A-pattern was 17.53 +/- 5.82 PD (index of surgical effect, 0.7). Subjective measurement of torsion was more consistent with the synoptophore compared with the double Maddox rod test. Objective measurement of torsion (fundus photography) was higher compared with subjective measurement. Postoperatively, there was insignificant change in the amount of torsion in upgaze and primary position. CONCLUSION: Posterior tenectomy of the superior oblique results in significant and controlled weakening of the superior oblique and collapse of the A-pattern with a clinically insignificant change in the amount of torsion.

Accuracy of visual assessment by school teachers in school eye screening program in delhi.

BACKGROUND: Although school eye screening is a major activity of the National Program for Control of Blindness, inadequate evidence exists about accuracy of school teachers in screening. OBJECTIVES: Compare quality of referral for subnormal vision by school teachers and primary eye care workers (PECW) in school children and to establish appropriate cutoff for identification of subnormal vision in school going children. MATERIALS AND METHODS: This was a cross-sectional study involving school children studying in classes 1 to 9 in different schools of Delhi evaluated for sub-normal vision. Vision was recorded by the teacher and a primary eye care worker especially trained for the study using the optotypes of Early treatment Diabetic Retinopathy Survey (ETDRS) vision chart with standard lighting. RESULTS: The total number of children enlisted in the 20 selected schools was 10,114. Of these, 9838 (97.3%) children were examined in the study. The mean age of children enrolled in the study was 11.6 ± 2.19 years with 6752 (66.9%) males. The sensitivity and specificity of teachers in comparison to PECW using 6/9.5 vision level as cutoff for referral was 79.2% and 93.3%, respectively compared to 77.0% and 97.1%, respectively on using the 6/12 optotype. The results showed significantly higher sensitivity and lower specificity for private schools against government schools and for older against younger children. CONCLUSIONS: Our results show that the use of teachers and shift to use of the 6/12 sized "E" for the school eye screening (SES) program is appropriate and would substantially reduce the work of eye care providers while improving its overall efficiency.

Prevalence of myopia and its risk factors in urban school children in Delhi: the North India Myopia Study (NIM Study).

PURPOSE: Assess prevalence of myopia and identify associated risk factors in urban school children. METHODS: This was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision <6/9.5, wearing spectacles and for a subset (10%) of randomly selected children with normal vision. All children with vision <6/9.5 underwent cycloplegic refraction. The prevalence of myopia <-0.5 diopters was assessed. Association of risk factors and prevalence of myopia was analyzed for children with myopia and randomly selected non myopic children and adjusted odds ratio values for all risk factors were estimated. RESULTS: A total number of 9884 children were screened with mean age of 11.6 + 2.2 years and 66.8% boys. Prevalence of myopia was 13.1% with only 320 children (24.7%) wearing appropriate spectacles. Mean myopic spherical error was -1.86 + 1.4 diopters. Prevalence of myopia was higher in private schools compared to government schools (p<0.001), in girls vs. boys (p = 0.004) and among older (> 11 years) children (p<0.001). There was a positive association of myopia with studying in private schools vs. government schools (p<0.001), positive family history (p< 0.001) and higher socio-economic status (p = 0.037). Positive association of presence of myopia was observed with children studying/reading > 5 hours per day (p < 0.001), watching television > 2 hours / day (p < 0.001) and with playing computer/video/mobile games (p < 0.001). An inverse association with outdoor activities/playing was observed with children playing > 2 hours in a day. CONCLUSION: Myopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies.

An optic nerve hypoplasia and coloboma in a patient with hemifacial microsomia.

Posterior segment anomalies are rare features of the oculoauriculovertebral complex. Our patient had hemifacial microsomia with an optic nerve hypoplasia in one eye and an optic nerve coloboma in the other eye. The optic nerve hypoplasia was ipsilateral to the side with hemifacial microsomia and microtia.