Pneumococcal vaccination in developing countries.
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Publications and source records attributed to Samir K Saha.
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BACKGROUND: Quinolone-induced arthropathic toxicity in weight-bearing joints observed in juvenile animals during preclinical testing has largely restricted the routine use of ciprofloxacin in the pediatric age group. As histopathologic, radiologic and magnetic resonance imaging monitoring evidence has gathered supporting the safety of fluoroquinolones in children, many pediatricians have started to prescribe quinolones to some patients on a compassionate basis. OBJECTIVE: The objective of this study was to ascertain the safety of ciprofloxacin in preterm neonates <33 weeks gestational age treated at Dhaka Shishu (Children) Hospital in Bangladesh. METHODS: Long-term follow up was done to monitor the growth and development of preterm infants who were administered intravenous ciprofloxacin in the neonatal period. Ciprofloxacin was used only as a life-saving therapy in cases of sepsis produced by bacterial agents resistant to other antibiotics. Another group of preterm neonates with septicemia who were not exposed to ciprofloxacin, but effectively treated with other antibiotics and followed up, were matched with cases for gender, gestational age and birth weight and included as a comparison group. Forty-eight patients in the ciprofloxacin group and 66 patients in the comparison group were followed up for a mean of 24.7 +/- 18.5 months and 21.6 +/- 18.8 months, respectively. RESULTS: No osteoarticular problems or joint deformities were observed in the ciprofloxacin group during treatment or follow up. No differences in growth and development between the groups were found. CONCLUSIONS: Ciprofloxacin is a safe therapeutic option for newborns with sepsis produced by multiply resistant organisms.
BACKGROUND: The advent of colour-coded tissue velocity echocardiography (TVE) has now made it possible to quantify left ventricular (LV) functions in patients with systemic arterial hypertension (HTN). Hypothesis In this project, we have studied the cardiac effects of a single dose of orally administered valsartan in patients with known HTN. METHODS: Fifty-five patients with HTN with a mean age of 56 +/- 10 years were given an early morning dose of 80 mg valsartan withholding regular antihypertensive medications on the day of investigation. TVE images, acquired on VIVID systems were digitized for postprocessing of longitudinal and radial peak systolic velocities, strain rate, and systolic and diastolic time intervals before (pre) and 5 h after (post) administration of the drug. RESULTS: Blood pressure (mmHg) pre and post, respectively, were 147 +/- 15 versus 137 +/- 14 systolic and 90 +/- 7 versus 86 +/- 7 diastolic (all P<0.01). LV longitudinal systolic velocities (cm s(-1)) were significantly higher post in LV septum (5.7 +/- 1.1 versus 6.4 +/- 1.6; P<0.001) with similar results obtained in other LV walls. Radial strain rate (1 s(-1)) was significantly higher post compared with pre valsartan (2.1 +/- 0.6 versus 2.3 +/- 0.9; P<0.01). Regional diastolic filling and ejection times (ms) were significantly shorter post (390 +/- 122 versus 370 +/- 120 and 275 +/- 32 versus 163 +/- 36 respectively; all P<0.05). CONCLUSIONS: Within 5 h after oral administration of valsartan, improvement in regional myocardial systolic functions could be registered. Although the changes could well be secondary to afterload reduction, additional effects of the drug, evidenced by improved strain rate that is relatively load-independent, may have contributed in this improvement.
Highly ciprofloxacin-resistant (MIC, 512 microg/ml) strains of Salmonella enterica serovar Typhi were isolated from the blood of typhoid patients in Dhaka, Bangladesh. The strains were indistinguishable by their antibiograms, biotypes, and variable-number tandem repeat types and had matching point mutations at positions 83 and 87 of the gyrA gene. The isolation of these strains in an area of high endemicity indicates the need for continuous surveillance of antibiotic resistance of S. enterica serovar Typhi and for the rationalized use of ciprofloxacin.
BACKGROUND: Haemophilus influenzae type b (Hib) diseases are responsible for an estimated 400,000 childhood deaths, mostly in developing countries. OBJECTIVES: To determine the value of the Wellcogen quantitative latex agglutination test (LA) in urine for the diagnosis of Hib pneumonia and meningitis. METHODS: Healthy and sick children aged <5 y were enrolled in Dhaka Shishu (Children's) Hospital. Boiled and non-concentrated urine specimens underwent LA testing. In vaccinated subjects, urine was tested by LA at 24 h, 4-6 and 7-10 d after vaccination. RESULTS: Of 1302 enrolled cases, 201 were healthy (90 Hib vaccine recipients and 111 provided NP) and 1101 were sick with either pneumonia (n=974) or meningitis (n=127). Among the healthy children enrolled, 41 (41/111, 37%) were colonised with Hib and two (2/41, 5%) were positive by LA test. Hib antigenuria among the children who had received Hib vaccination was mainly detected only on day 1 (7/90, 8%) of vaccination. Among the sick children, LA test for Hib antigen was positive for all confirmed cases of Hib pneumonia (10) and meningitis (35). In contrast, none of the urine specimens from the cases with a known aetiology other than Hib (n=104) was positive. Quantitative analysis of antigenuria of sick children showed that it is positive at least up to 1:8 and 1:16 dilutions for pneumonia and meningitis, respectively, in contrast with or=1:8 dilutions. CONCLUSIONS: The Wellcogen LA test for Hib using boiled and non-concentrated urine is more sensitive than blood culture alone and is highly specific.
Meningitis is a serious problem in newborn infants and has high mortality and frequent neurological sequelae. In neonates, signs and symptoms of serious infections are often obscure and clinical examination cannot distinguish septicemic babies with or without meningitis. Therefore, lumbar puncture is often not done in time and thus diagnosis of meningitis is missed. This study aimed to discover the prevalence of meningitis among these cases based on laboratory investigation. We prospectively enrolled the blood culture positive septicaemia cases which were not labeled as cases of meningitis during routine clinical evaluation. Out of 30 septicemic cases, eight (26.7%) had abnormal CSF cytology and biochemistry suggestive of meningitis. Among these eight cases, four had positive CSF culture; [Klebsiella pneumoniae (n = 3) and Pseudomonas aeruginosa (n = 1)], which were similar to the blood isolate of the respective patient. The clinical manifestations were similar in both septicemia and meningitis cases. Mortality was high among the meningitis cases compared with those having septicemia alone (37.5% vs. 13.3%), indicating the need for early diagnosis of this disease. Our data confirmed that it is important to do a lumbar puncture, along with blood culture, for all suspected septicemia cases.
BACKGROUND: The appropriate evaluation of atrial electrical function is only possible by means of invasive electrophysiology techniques, which are expensive and therefore not suitable for widespread use. Mechanical atrial function is mainly determined from atrial volumes and volume-derived indices that are load-dependent, time-consuming and difficult to reproduce because they are observer-dependent. AIMS: To assess the feasibility of tissue velocity echocardiography (TVE) to evaluate atrial electromechanical function in young, healthy volunteers. SUBJECTS AND METHODS: We studied 37 healthy individuals: 28 men and nine women with a mean age of 29 years (range 20-47). Standard two-dimensional (2-D) and Doppler echocardiograms with superimposed TVE images were performed. Standard echocardiographic images were digitized during three consecutive cardiac cycles in cine-loop format for off-line analysis. Several indices of regional atrial electrical and mechanical function were derived from both 2-D and TVE modalities. RESULTS: Some TVE-derived variables indirectly reflected the atrial electrical activation that follows the known activation process as revealed by invasive electrophysiology. Regionally, the atrium shows an upward movement of its walls at the region near the atrio-ventricular ring with a reduction of this movement towards the upper levels of the atrial walls. The atrial mechanical function as assessed by several TVE-derived indices was quite similar in all left atrium (LA) walls. However, all such indices were higher in the right (RA) than the LA. There were no correlations between the 2-D- and TVE-derived variables expressing atrial mechanical function. Values of measurement error and repeatability were good for atrial mechanical function, but only acceptable for atrial electrical function. CONCLUSION: TVE may provide a simple, easy to obtain, reproducible, repeatable and potentially clinically useful tool for quantifying atrial electromechanical function.
OBJECTIVE: To determine the prevalence, age-group distribution, serotype, and antibiotic susceptibility patterns of invasive Haemophilus influenzae type b (Hib) isolates in Bangladeshi children because data regarding Hib diseases in developing countries are scarce, which has led to delay of the introduction of Hib vaccine in these countries. METHODS: Children diagnosed with meningitis (n = 1412) and pneumonia (n = 2434) were enrolled in this surveillance study for Hib invasive diseases. Cerebrospinal fluid (CSF) and blood specimens, and the subsequent isolates, were processed using standard procedures. RESULTS: During 1993 to 2003, 455 H influenzae strains were isolated from patients with meningitis (n = 425) and pneumonia (n = 30), and an additional 68 Hib meningitis cases were detected by latex agglutination (LA) testing. Overall, 35% of pyogenic meningitis cases were a result of H influenzae, 97.1% of which were Hib. Most (91.4%) cases occurred during the first year of life. Resistance to ampicillin, chloramphenicol, and cotrimoxazole was 32.5%, 21.5%, and 49.2%, respectively. There was a trend toward increasing resistance for all three drugs. Resistance to ampicillin and chloramphenicol was almost universally coexistent and was associated with increased sequelae compared with the patients infected with susceptible strains (31% [23/75] vs 11% [21/183]; P <.001). CONCLUSION: Hib is the most predominant cause of meningitis in young Bangladeshi children. Resistance to ampicillin and chloramphenicol and the high cost of third-generation cephalosporin highlight the importance of disease prevention through vaccination against Hib.
OBJECTIVE: The skin is a potential source for invasive infections in neonates from developing countries such as Bangladesh, where the level of environmental contamination is exceedingly high. A randomized controlled trial was conducted from 1998 to 2003 in the Special Care Nursery of a tertiary hospital in Bangladesh to test the effectiveness of topical emollient therapy in enhancing the skin barrier of preterm neonates less than 33 weeks of gestational age. In the initial months of the study, the infection and mortality rates were noted to be unacceptably high. Therefore, an infection control program was introduced early in the trial to reduce the rate of nosocomial infections. STUDY DESIGN: After a comprehensive review of neonatal care practices and equipment to identify sources of nosocomial infections, a simple but comprehensive infection control program was introduced that emphasized education of staff and caregivers about measures to decrease risk of contamination, particularly hand-washing, proper disposal of infectious waste, and strict asepsis during procedures, as well as prudent use of antibiotics. RESULTS: Infection control efforts resulted in declines in episodes of suspected sepsis (47%), cases of culture-proven (61%) sepsis, patients with a clinical diagnosis of sepsis (79%), and deaths with clinical (82%) or culture-proven sepsis (50%). CONCLUSION: The infection control program was shown to be a simple, low-cost, low-technology intervention to reduce substantially the incidence of septicemia and mortality in the nursery.
BACKGROUND: Streptococcus pneumoniae is the leading cause of childhood pneumonia and meningitis worldwide. Isolation of this organism, however, is uncommon in resource-poor countries, in part because of extensive use of prior antibiotics. A rapid, highly sensitive immunochromatographic test (ICT) for S. pneumoniae was evaluated for the diagnosis of meningitis. METHODS: Cerebrospinal fluid (CSF) from 450 children with suspected meningitis was tested with ICT, and results were compared with CSF culture, latex agglutination test (LAT) and/or polymerase chain reaction (PCR). Serial CSF specimens from 11 patients were also evaluated for duration of positive results during effective antimicrobial therapy. FINDINGS: All 122 cases of pyogenic pneumococcal meningitis positive either by culture (N = 87) or PCR (N = 35) were positive by ICT, yielding 100% (122 of 122) sensitivity. All purulent CSF specimens from patients with meningitis caused by other bacteria by culture (N = 149) or by LAT (N = 48) or those negative by culture, LAT and LytA and thus of unknown etiology (N = 20), and normal CSF specimens (N = 104) were negative by ICT. Thus the specificity of ICT also was 100% (321 of 321), although negativity of ICT was not confirmed by PCR, if it was positive for other organisms either by culture or LAT. Serotyping of S. pneumoniae strains revealed 28 different serotypes, indicating that outcome of ICT are independent of diverse capsular serotype of pneumococcus. Antigen was detected by ICT for at least 10 days after presentation, and 1 was still positive on day 20, which was longer than for either LAT or PCR. INTERPRETATION: ICT for pneumococcal antigen in CSF is 100% sensitive and specific in diagnosing pyogenic pneumococcal meningitis and can detect approximately 30% more pneumococcal meningitis cases than with culture alone. The simplicity of the test procedure and the longevity of CSF antigen detection suggest the potential utility of ICT to estimate the true burden of pneumococcal disease, as for Haemophilus influenzae type b using data from meningitis, and to guide selection of appropriate antibiotic treatment, especially in resource-poor countries with widespread prehospital antimicrobial use.
Primary renal tumors with intracardiac metastasis are not infrequent. Most of the secondary spread is blood-borne and occurs via inferior vena cava. Patients with such a spread often present with cardiac symptoms. We presume that a metastatic spread in the right atrium through coronary sinus has never been reported in the literature according to the result of a Medline search at the time of writing this report.
Tissue-Doppler echocardiography (TDE) has been introduced to quantify stress echocardiography by means of assessing the left ventricular (LV) segmental myocardial velocities and excursion. The interaction between LV long- and short-axis function during physical exercise has not been elucidated completely. The aim of the present study was to investigate long- and short-axis LV function, as assessed by myocardial velocities and excursions at rest and during exercise and its possible relationship with heart rate in healthy elderly individuals by TDE. Twenty-seven individuals underwent an exercise test in the supine position on a bicycle ergometer. The initial workload was 30 Watts, followed by 20-Watt increments every third minute. Standard echocardiographic images with super-imposed colour TDE were digitized at the end of each step. The following variables were studied in the LV long- and short-axis: myocardial peak systolic velocity (PSV) and excursion, isovolumic contraction and relaxation times, peak velocity at early diastole (E'-wave) and peak velocity at late diastole (A'-wave) and the E'/A' ratio. Increments in myocardial peak systolic velocity and excursion in the LV long-axis were more pronounced during low workloads. The increase in those variables in the short-axis occurred mainly at higher exercise loads. The improvement in LV long- and short-axis functions was closely related to the increase in the heart rate. Shortening of the isovolumic contraction and relaxation times occurred only at the initial stages of exercise. An increase in the long-axis E'/A' ratio occurred during exercise, whereas this ratio was unchanged in the short-axis. In conclusion, during exercise, the LV long- and short-axis functions behave differently, and increases in LV long- and short-axis functions are related to changes in heart rate. Therefore, in the interpretation of echocardiographic findings during exercise stress echocardiography, these facts have to be taken into account.
BACKGROUND: Dobutamine stress echocardiography (DSE) quantified by tissue Doppler (TVI) have improved the diagnostic capacity of the procedure. Quantification of other stress modalities, e.g. adenosine stress echo (ASE) and exercise stress echocardiography (ESE) are necessary for assessing any pathophysiological differences in different forms of stress. METHODS: Ten healthy individuals underwent ASE, DSE, and ESE during a span of 2-5 days. Left ventricular (LV) apical images at rest and peak stress (max) were postprocessed using TVI on a GE System FiVe equipment. ECG-derived QRS duration (QRSD, ms), heart rate (HR, bpm), TVI-estimated basal systolic velocities (S2V, cm s(-1)), ejection time (S2T, ms) and strain (S, %) were computed off-line and compared. Longitudinal displacement imaging, tissue tracking, was also made. RESULTS: Data for ASE, DSE and ESE during peak stress were (HR: 84 +/- 12***, 142 +/- 19, 137 +/- 27; P<0.001) (QRSD: 92 +/- 18**, 74 +/- 13, 79 +/- 9; P<0.05), (S2T: 307 +/- 34***, 175 +/- 53, 192 +/- 25; P<0.001) and (S%: 26.0 +/- 3.0, 21.2 +/- 7.3, 22.1 +/- 5.1; P = n.s.) respectively. Velocity response, registered in the LV septum at max, was lowest during ASE (7.4 +/- 1.4) highest during DSE (13.0 +/- 2.7; P<0.001 versus ASE) and somewhat intermediate during ESE (11.3 +/- 3.5; P<0.001 versus ASE). In contrast, strain and displacement did not differ. CONCLUSION: ASE evokes significantly less LV systolic response compared with both DSE and ESE. Increased velocity (P<0.05 versus rest) and strain (P>0.05) response at a much lower HR indicates that adenosine has minor effects on contraction presumably secondary to vasodilatation. Powerful chronotropic response to DSE and ESE is probably prerequisite for strong velocity response at the expense of strain and displacement. TVI-assisted stress echocardiography thereby shows different LV systolic response in healthy individuals, depending on stress modality.
Hepatitis B virus (HBV) infection is one of the most prevalent public health problems worldwide, and causes 1 million deaths annually. In Bangladesh, information about prevalence of HBV infection is scarce, and there is no available data on HDV infection. We determined rates of HBsAg and anti-HBc seropositivity in asymptomatic, healthy children (n = 181) and adults (n = 354) presenting to referral facilities in Dhaka, Bangladesh, and tested a separate group of HBsAg-positive patients (n = 180) for prevalence of HDV. Testing of serum was also performed for signs of liver disease. Overall, seropositivity of HBsAg and anti-HBc in studied subjects was 3 per cent (16/534) and 21.1 per cent (113/534), respectively. Prevalence of HBsAg was highest in the 5- to 9-year-old (8.5 per cent, 7/82) and 10- to 14-year-old (5.9 per cent, 2/34) age groups. Unlike HBsAg, prevalence of anti-HBc was lower in children (14.9 per cent in those below the age of 15) than adults (24.4 per cent in those aged 20-34 years) (p < 0.05). Most HBsAg-positive individuals were symptomatic (n = 125, 69.4 per cent). A high rate (24.4 per cent, 44/180) of simultaneous infection with HDV was observed among HBsAg-positive subjects, with higher rates in older individuals. Anti-HDV seropositivity rate was similar among asymptomatic (21.8 per cent, 12/55) and symptomatic (25.6 per cent, 32/125) HBsAg carriers. Our data suggest that Bangladesh is of moderate endemicity for HBV infection, and has relatively high rates of co-infection with HDV. Control HBV and HDV infection in Bangladesh may be best achieved by targeting preschool children, which could fit readily within the existing EPI schedule.
The nasopharyngeal carriage of Streptococcus pneumoniae is thought to pose a risk for invasive pneumococcal diseases, and the evaluation of carriage strains is thus often used to inform antibiotic treatment and vaccination strategies for these diseases. In this study, the age-specific prevalences, resistance to antibiotics, and serotype distributions of 1,340 carriage strains were analyzed and compared to 71 pneumococcal strains isolated from the cerebrospinal fluid of children under 5 years old with meningitis. Overall, the nasal carriage rate was 47%. One-fourth (26%) of the infants under 1 month of age and one-half (48%) of the infants under 12 months of age were colonized with S. pneumoniae. Rural children were colonized earlier than those from urban areas. Approximately one-fourth and one-half of the cases of pneumococcal meningitis occurred in the first 3 and 6 months of life, respectively. The respective rates of resistance for carriage and meningitis strains to penicillin (7 and 3%), cotrimoxazole (77 and 69%), and erythromycin (2 and 1%) were similar, whereas chloramphenicol resistance was lower among carriage strains (3%) than among meningitis strains (15.5%). The predominant serogroups of carriage and invasive isolates were variable and widely divergent. Thus, hypothetical 7-, 9-, and 11-valent vaccines, based on the predominant carriage strains of the present study, would cover only 23, 26, and 30%, respectively, of the serotypes causing meningitis. Further, currently available 7-, 9-, and 11-valent vaccines would protect against only 26, 43, and 48%, respectively, of these meningitis cases. In conclusion, while the surveillance of carriage strains for resistance to antibiotics appears useful in the design of empirical treatment guidelines for invasive pneumococcal disease, data on the serotypes of carriage strains have limited value in vaccine formulation strategies, particularly for meningitis cases.
Data on the seroprevalence of antibodies protective against the varicella-zoster virus are needed to develop strategies to prevent varicella infections in Bangladesh. Of 1209 patients evaluated at referral-level health facilities in Dhaka, 943 (78%) had no known history of chickenpox and were tested by latex agglutination for the presence of varicella-zoster antibody in serum. Forty-one per cent (386) of the 943 specimens tested were negative. Seropositivity was highest among neonates (83%), declined sharply to 19% in those aged 7-12 months, and thereafter rose steadily with age until a plateau of 85% was reached after the age of 16 years. This first report of varicella-zoster antibody seroprevalence in Bangladesh suggests that, as in other tropical areas, a significant proportion of children, adolescents and adults are susceptible. Children aged from 15 months to early adolescence might be the most important group to target with the vaccine currently available. However, to ensure successful immunisation, further, population-based seroprevalence data are needed, as are an assessment of the vaccine's acceptability and the accessibility of the target population. Incomplete coverage of young children could result in delayed acquisition, and, ultimately, in more severe disease.
Topical application of natural oils is practised routinely in many countries and may either improve skin barrier function and health or have detrimental cutaneous and systemic effects, depending on the composition of the oil. Little literature on the epidemiology, practice, and perceptions of traditional neonatal oil massage is available. This study was undertaken to gain insights into the epidemiology, practice, and perceptions regarding traditional oil massage of Bangladeshi neonates. A questionnaire was administered verbally to the primary caretaker of 332 outpatients at the Dhaka Shishu Hospital, and to 20 women with children encountered at the Matlab Health Complex in Bangladesh. More than 96% (340/352) of the caregivers practised oil massage, irrespective of socioeconomic status and place of residence. Among those at the Dhaka Shishu Hospital who practised oil massage, mustard oil was used alone or in combination by 95% (303/320) over the entire body, 1-3 time(s) daily (96%), starting in the first three days of life (72%) in both term and preterm neonates. Perceived benefits included prevention of infections (69%) and hypothermia (2%). Oil massage is an important traditional domiciliary practice used annually on more than three million newborns in Bangladesh. Given its potential for beneficial and harmful effects, further research is needed on the value of this practice, and ways to optimize its beneficial effects.