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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 7  |  Issue : 3  |  Page : 156-161

Clinico-bacteriological profile and outcome of children with pneumonia under 5 years of age


Department of Pediatrics, Government Medical College, Haldwani, Nainital, Uttarakhand, India

Date of Submission16-Mar-2020
Date of Decision11-Jun-2020
Date of Acceptance23-Sep-2020
Date of Web Publication25-Jan-2021

Correspondence Address:
Ritu Rakholia
Department of Pediatrics, Government Medical College, Medical College Campus, Type 4, H5, Haldwani, Nainital, Uttarakhand
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/cjhr.cjhr_20_20

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  Abstract 


Context: India has the highest mortality due to pneumonia in the world. Despite advances in management, it still continues to be major cause of under 5 mortality in children with pneumonia. Aims: The aim of this study was to assess the clinico-bacteriological profile and outcome associated with pneumonia in Uttarakhand, India. Settings and Design: This was a prospective hospital-based observational study. Materials and Methods: Two hundred and sixteen children 1 month to 5 years of age, fulfilling the WHO criteria of pneumonia over a period of 18 months, were studied. Clinical profile, blood culture, and outcome were evaluated as per predesigned pro forma. Statistical Analysis: Data were analyzed using the Chi-square test. Results: Most of the patients were infants (65.28%, n = 141) and males (58.8%, n = 127). Cough (98.15%, n = 212), fever (91.67%, n = 198), difficulty in breathing (76.39%, n = 165), and crepitations (97.22%, n = 210) were the most common clinical pictures. Blood culture positivity was 21.3% (n = 46), more in infants (24.8%, n = 35) as compared to 1–5 years of age. Staphylococcus aureus (39.13%, n = 18) was the most common organism, followed by Gram-negative bacilli (26.09%, n = 12). Lack of exclusive breastfeeding (33.3%, n = 72), incomplete immunization (54.2%, n = 117), exposure to smoke (6.02%, n = 13), and malnutrition (26.39%, n = 57) were significantly associated with severe pneumonia (P < 0.05). Bronchopneumonia seen as fluffy infiltrates was seen in 72.2% (n = 156). Bubble Continuous Positive Airway Pressure (CPAP) was provided in 26% (n = 52), ventilation 14% (n = 28), and change of antibiotics was done in 29.5% (n = 59). Mortality was 8.8% (n = 18). Conclusions: This study highlights increasing incidence of S. aureus as a causative organism, especially in infants. We recommend updating antibiotic guidelines and liberal use of CPAP for better outcome. Infancy, lack of exclusive breastfeeding, incomplete immunization, malnutrition, anemia, and exposure to smoke are key domains that should be addressed for decreasing severity of pneumonia and its better outcome.

Keywords: Children, outcome, pneumonia, Staphylococcus aureus


How to cite this article:
Bathla A, Rakholia R, Choudhary B, Arya A. Clinico-bacteriological profile and outcome of children with pneumonia under 5 years of age. CHRISMED J Health Res 2020;7:156-61

How to cite this URL:
Bathla A, Rakholia R, Choudhary B, Arya A. Clinico-bacteriological profile and outcome of children with pneumonia under 5 years of age. CHRISMED J Health Res [serial online] 2020 [cited 2021 Feb 26];7:156-61. Available from: https://www.cjhr.org/text.asp?2020/7/3/156/307820




  Introduction Top


Pneumonia is a leading cause of childhood morbidity and mortality globally. It accounts for 15% of all deaths of children under 5 years old, killing 808694 children in 2017.[1] A systematic review in 2010 estimated 0.22 pneumonia episodes per child year in developing countries, with 11.5% progressing to severe disease.[2] Death due to pneumonia has declined from 1.7 million in 2000 to 802,000 in 2018 but at a significantly lower rate than due to other childhood illnesses such as malaria, measles, and HIV.[3] With 179,000 deaths in 2015 in children under 5 years of age, India has the highest deaths due to pneumonia in the world.[4] Globally, there are over 1400 cases of pneumonia per 100,000 children, with the greatest incidence occurring in South Asia (2500 cases per 100,000 children).[3]

Most cases of pneumonia are caused by microorganisms, among which Streptococcus pneumoniae is the most common bacterial pathogen.[1] However, there are some noninfectious causes which include aspiration, hypersensitivity reactions, and drug- or radiation-induced pneumonitis. In recent decades, there is a shift from bacterial to viral predominance in developed countries due to hygiene sanitation, infection control, and vaccination strategies. Recent changes such as implementation of Haemophilus influenzae Type B vaccine and introduction of pneumococcal vaccine and HIV pandemic may have altered the distribution of implicated pathogens.[5] A systematic review from India suggested S. pneumoniae as a causative agent in 15%–24% of bacterial pneumonia.[6] Most of the studies were conducted in the developed world while studies from developing countries are still scarce which have the maximum burden of disease. Broad range of presenting features and absence of gold standard diagnostic test makes diagnosis of childhood pneumonia difficult.

The study on clinical and bacteriological profile would help in identifying common causes of pneumonia, most of which are bacterial pathogens whose rapid identification can influence individual treatment and better choice of opting antibiotics and rationalize immunization policy at national level.


  Materials and Methods Top


The present study is a prospective, single centered study conducted in the pediatric ward of a teaching tertiary care hospital, Haldwani, Uttarakhand, with inclusion of enrollment of children aged 1 month to 5 years admitted to the hospital fulfilling the World Health Organization (WHO) Integrated Management of Childhood Illness case definition of community-acquired pneumonia over a period from October 2017 to March 2019. Fast breathing with or without chest indrawing is called pneumonia, and fast breathing with any of danger signs such as inability to drink, persistent vomiting, lethargic or unconscious, stridor in a calm child, or severe malnutrition is referred to as severe pneumonia. Tachypnea was defined by the WHO as a respiratory rate of >60/min for children <2 months, >50/min for children between 2 and 12 months, >40/min for children between 12 and 59 months OR children aged 1 month to 5 years admitted to the hospital with chest retractions AND chest X-ray findings of pneumonia as described by the WHO.[7] as consolidation, other infiltrates and pleural effusion. Dense or fluffy opacities occupying a portion or whole of a lobe or of the entire lung known as consolidation OR pleural effusion that is in the lateral pleural space and other infiltrates defined as linear and patchy densities in a lacy pattern involving both lungs featuring peribronchial thickening and multiple areas of atelectasis.

Children with history of hospitalization in the past 30 days, those on mechanical ventilation, whose parents refuse consent, and age >5 years were excluded. A sample size of 216 children with pneumonia in the age group of 1 month to 5 years admitted in the pediatric ward of Dr. Sushila Tiwari Memorial Government Hospital, Haldwani, were included in the study in accordance with the inclusion/exclusion criteria.

Consent was taken from the parents/guardian of each patient enrolled. They were explained the aim of this study, the investigations that would be involved, and the clinical details that would be obtained from the patients. The study protocol was approved by the Institutional Ethical Committee.

A detailed history and examination of all children was conducted to look for the presence of danger signs and risk factors of severe disease, like lack of exclusive breastfeeding, exposure to tobacco smoke and lack of complete immunization and relevant hematological investigations was done. Chest X-ray was done for each child before starting treatment.

Blood culture samples were taken from all patients. Using proper aseptic technique, 1–3 ml of venous blood was collected in Pediatric Plus bottles. The culture bottles showing signs of growth were subcultured on blood, MacConkey, and chocolate agar and incubated overnight at 37°C. The colonies detected were further identified by standard biochemical tests. Patients with pleural effusion underwent thoracentesis under sonographic guidance after written informed consent. Aspirated pleural fluid was then sent for culture and Gram's staining, biochemistry, and cytology.

The main outcome measures the description of symptoms and signs, risk factors, need of CPAP or mechanical ventilation, and fate of each admitted patient and the detection of bacteria by blood or pleural fluid culture.

Statistical analysis

The data were entered in MS Excel spreadsheet, and analysis was done using the Statistical Package for the Social Sciences version 21.0 (IBM, Chicago, USA). Categorical variables were presented in number and percentage (%) and continuous variables were presented as mean ± standard deviation (SD) and median. Qualitative variables were correlated using the Chi-square test.


  Results Top


A total of 216 children admitted with pneumonia, in the age group of 1 month to 5 years, over a period of 1.5 years were enrolled. [Figure 1] shows the outcome of patients with pneumonia.
Figure 1: Flowchart depicting outcome of pneumonia patients

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[Table 1] presents the baseline characteristics of patients. The mean age of children enrolled in our study was 15.64 ± 15.92 months. Most of the patients were infants (65.28%) and 127 (58.80%) males. According to the Revised WHO classification (2014), pneumonia was seen in 164 (75.93%) children and severe pneumonia in 52 (24.07%) children. One hundred and sixteen (53.7%) cases of pneumonia presented in the winter season. Malnutrition defined as weight for height <2 SD was present in 57 (26.39%) while severe acute malnutrition defined as weight for height <3 SD was present in 16 (7.4%) cases. History of smoke exposure was present in 13 (6.02%) cases. One hundred and seventeen (54.2%) were partial or incompletely immunized as per national immunization schedule. Incomplete immunization with pentavac-1 was 14.42% (n = 30), pentavalent-2 was 24.1% (n = 45), and pentavalent-3 was 36% (n = 63).
Table 1: Baseline characteristics of children enrolled in the study

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[Figure 2] shows the symptoms, signs, and radiographic findings. We found clinical triad of cough in 98.15% (n = 212), fever 91.67% (n = 198), and difficulty in breathing in 76.39% (n = 165) of the patients. Pallor was present in 174 (80.56%) cases, and in 146 cases, etiology ascertained was iron-deficiency anemia. Crepitations were the most consistent sign present in 210 (97.22%) cases.

Radiological findings are shown in [Figure 3]. [Table 2] summarizes the association of risk factors with severity of pneumonia. Lack of exclusive breastfeeding, incomplete immunization, exposure to smoke, pallor, cyanosis, malnutrition, and severe acute malnutrition were significantly associated with severe pneumonia.
Figure 2: Clinical profile of children with pneumonia

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Figure 3: X-ray findings in children with pneumonia

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Table 2: Association of risk factors with severity

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Using blood culture, bacteria could be identified in 46/216 (21.3%) cases. [Table 3] summarizes organisms identified using blood culture. Staphylococcus aureus was the most common organism isolated in 18 (39.13%) cases, followed by Gram-negative bacilli (GNB) (Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae) in 12 (26.09%) cases, while S. pneumonia was seen only in 2 (4.35%) cases. In our study, blood culture positivity was 24.4%, 25%, and 14.7% in the age group of 1 month to 3 months, 3 months to 1 year, and 1 year to 5 years, respectively. Predominant organism isolated was S. aureus followed by GNB in the age group of 1–3 months and S. aureus in the age group of 3 months to 1 year and in the age group of 1 to 5 years Micrococcus followed by S. pneumonia. Pleural fluid showed methicillin-resistant S. aureus (MRSA) in 66.67% (n = 2) of the cases.
Table 3: Organisms identified in blood culture

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The mean stay of patients admitted with pneumonia was 8.77 ± 4.24 days ranging from 1 to 32 days. Out of 200 cases who took complete treatment in our hospital, stay was of <7 days in 88 (44%) cases and more than 7 days in 112 (56%) cases. Respiratory support through CPAP machine or bubble CPAP was provided in 52 cases (26%), and ventilation was required in 28 (14%) cases out of 200 cases. Change of antibiotics was done in 59 (29.5%) cases. Out of 216 cases, 16 (7.41%) were discharged against medical advice. One hundred and eighty-one (83.8%) improved after treatment and discharged, and 19 (8.8%) cases died during hospital stay. Out of 19 total deaths, 8 (42.11%) cases died within 24 h, 5 (26.32%) cases died in 24–48 h, and 6 (31.58%) cases died after 48 h.


  Discussion Top


In our study, 65.28% (n = 141) of the children with pneumonia were infants (1 month to 1 year) which is slightly more than studies with an incidence ranging from 40.5%[8] to 53.5%.[9] This suggests that infants are particularly vulnerable to pneumonia. Hence, respiratory symptoms in this age group should be carefully monitored and aggressively managed if morbidity and mortality due to pneumonia is to be reduced. 58.8% (n = 127) of all cases were male. This male predominance also exists in other Indian studies[8],[9] and may be because of bias in treatment-seeking behavior of parents.

In our study, 24.07% (n = 52) were diagnosed with severe pneumonia according to the Revised WHO Classification (2014) similar to other Indian studies.[10],[11] In our study, 53.7% (n = 116) of the cases occurred in winter similar to a study in the USA. and in England and Wales.[12],[13] This might be because of seasonal epidemic of respiratory viruses. Hence, viral pneumonia, considering the seasonal variation, may be an important cause in this region too needing further studies. We were not able to identify viral etiology of pneumonia due to resource constraints as culture was positive for bacteria in only 22.2% (n = 48) of the cases.

In our study, fast breathing, fever, cough, difficulty in breathing, and noisy breathing were found in 100% (n = 216), 91.67% (n = 198), 98.15% (n = 212), 76.39% (n = 165), and 35.65% (n = 77) of the cases, respectively, similar to Mathew et al.[8] and Jain et al.[12] who found fever in 91% and cough in 95%. Retractions were seen in 62% of the children in our study, of which 12.96% had suprasternal retractions. This suggests that fever, cough, and fast breathing are present in nearly all cases of childhood pneumonia. Noisy breathing and chest retractions are more frequently seen in infants with pneumonia than older children. In our study, crepitations were found in 97.22% of the cases, wheezing was found in 13.89% of the cases, and bronchial sounds were found in 5.09% of the cases similar to a study by Mathew et al.,[8] suggesting that crepitations are universal finding in pneumonia while wheezing and bronchial breathing are more commonly seen in older children and are not associated with severe pneumonia.

In our study, anemia (pallor) was found to be present in 80.56% (n = 174) of the cases similar to an Indian study,[11] comparatively more than NFHS-4[14] data showing 59.8% prevalence. In our study, blood picture and RBC indices in 84% of the cases of anemia were suggestive of iron deficiency. Iron profile could be done in 20.7% (n = 36) of the cases and confirmed iron-deficiency anemia. Anemia is a risk factor for pneumonia and its severity correlates with severity of pneumonia.

Malnutrition was found in 26.39% (n = 57) and severe acute malnutrition in 7.4% (n = 16) of the cases which is much lower than Indian studies.[8],[11],[15] Lack of exclusive breastfeeding was found in 33.3% (n = 72) of the cases, almost similar to other Indian studies,[11],[16] but less than NFHS-4[14] data of Uttarakhand showing it in 48.8% of the children. This might be due to lack of awareness of benefits of exclusive breastfeeding. Hence, the importance of antenatal and postnatal maternal counseling to ensure exclusive breastfeeding should be overemphasized to reduce morbidity and mortality due to pneumonia.

Smoke exposure was found in 6.02% of the patients in contrast to higher incidence of up to 30% in some studies.[8] This might be due to implementation of Pradhan Mantri Ujjwala Yojana (PMUY) launched by the Prime Minister of India on May 1, 2016.

Incomplete or no immunization was found in 45.83% of the cases similar to a study in Rajasthan.[15] Incomplete vaccination with pentavalent-1 was seen in 14.42% (n = 30), pentavalent-2 was seen in 24.1% (n = 45), and pentavalent-3 was seen in 36% (n = 63), more than NFHS-4[14] data showing incomplete immunization with 3 doses of DPT vaccine given earlier in 20.1% of the cases. This could have led to H. influenzae pneumonia, but we were not able to identify any H. influenza e due to fastidious nature of organism, and most children had received some form of antibiotics before reaching our tertiary care center. In our study, risk factors associated with severe pneumonia are lack of exclusive breastfeeding, anemia, and malnutrition, especially severe acute malnutrition. Incomplete immunization and exposure to smoke are other significant risk factors associated with morbidity and severity of pneumonia.

In our study, the most common clinical diagnosis at admission was bronchopneumonia in 72% (n = 156) seen as fluffy infiltrates on chest X-ray, followed by interstitial/viral pneumonia in 22.22% (n = 48), lobar pneumonia in 4.17% (n = 9), and pleural effusion in 1.39% (n = 3) of the cases. This is similar to a study from Rajasthan.[15] Other studies have a lower incidence of bronchopneumonia.[11]

In our study, S. aureus (predominantly MSSA) was the most common isolated bacteria, followed by GNB, while S. pneumoniae was isolated in only 4.35% (n = 2) of the cases.

Similar results were shown in recent Indian studies.[8],[15] In a study by Mathew et al.,[8] predominant organism belongs to S. aureus in 36.7% of the cases, followed by GNB in 32.7% of the cases and S. pneumoniae in 20.4% of the cases. In a study by Yudhavir et al.,[15] S. aureus was predominantly organism being 44.8%, followed by S. pneumonia and Pseudomonas in 13.8%.

No detection of H. influenzae may be because of fastidious conditions required for growth and lack of antigen and molecular-based diagnostic modalities or may be due to reduction in H. influenza pneumonia after inclusion of pentavalent vaccine in the Universal Immunization Program. Decreased detection of S. pneumoniae leading to comparatively increased detection of S. aureus in studies done in recent years may be probably because clinical pneumonia due to other pathogens mask the presence of S. pneumonia and its isolation rate could also be lower because of only culture as mean of isolation as we did not do polymerase chain reaction because of resource limitations and this being a tertiary level referral center, many patients had received antibiotics before admission. Pneumococcal vaccine is part of IAP immunization schedule, however, it is not part of the National Immunization Schedule in Uttarakhand. Increased vaccine use in private setup could have contributed to less S. pneumoniae.

A total of more than one-fifth (21.3%) of the patients with pneumonia showed a positive blood culture positivity, more in infants (approximately 25%) than older children (approximately 15%), and predominant organism identified was methicillin-sensitive S. aureus. Pleural fluid showed MRSA in two-third of the cases, similar to a study from Thailand.[17]

In our study, CPAP support was given in 26% (n = 52) of the cases and ventilator support was given in 14% (n = 28) of the cases much more than the study by Kumar et al.[11] showing CPAP in 10.5% of the cases and mechanical ventilation in 4.5% of the cases. Fifty-six percent of the cases had prolonged hospital stay of more than 7 days almost similar to other studies.[11],[16]

Mortality in our study was 8.8% lesser than other Indian studies.[8],[15],[16] Out of 19 deaths, 8 cases died within 24 h, 5 died between 24 and 48 h, and 6 died after 48 h of admission. Similar results were found by Tiewsoh et al.[16] showing 10 deaths within 24 h, 4 deaths between 24 and 48 h, and 7 deaths after 48 h.


  Conclusion Top


Pneumonia is one of the major causes of morbidity and mortality in children, especially in under 5 years of age. Fever, cough, and chest crepitation are present nearly in all cases of pneumonia but may be absent in young infants (<3 months) suggesting high sensitivity of symptoms and signs mentioned in the WHO ARI control program. Noisy breathing and chest retractions are most frequently seen in infants with pneumonia than older children (1–5 years). Wheezing and bronchial breathing are more commonly seen in older children and are not associated with severe pneumonia. Blood culture positivity was 21.3%, more in infants (24.8%) than older children, and predominant organism was S. aureus.

Lack of exclusive breastfeeding, incomplete immunization, exposure to smoke, malnutrition, and anemia are easily modifiable risk factors for severe pneumonia. Health planning authorities should target modifiable risk factors and ensure appropriate antibiotics and good supportive care to help India to forego its dubious distinction of being the country with the highest mortality due to pneumonia.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
World Health Organisation. Pneumonia Fact Sheet. Available from: http://www.who.int/news-room/fact-sheets/detail/pneumonia. [Last accessed on 2019 Aug 02].  Back to cited text no. 1
    
2.
Rudan I, O'Brien KL, Nair H, Liu L, Theodoratou E, Qazi S, et al. Epidemiology and etiology of childhood pneumonia in 2010: Estimates of incidence, severe morbidity, mortality, underlying risk factors and causative pathogens for 192 countries. J Glob Health 2013;3:10401-5.  Back to cited text no. 2
    
3.
UNICEF. Pneumonia in Children-UNICEF. Available from: https://data.unicef.org/topic/child-health/pneumonia/. [Last accessed on 2020 Mar 08].  Back to cited text no. 3
    
4.
UNICEF. Pneumonia and Diarrhoea -UNICEF. Available from: https://data.unicef.org/wp-content/uploads/2016/11/UNICEF- Pneumonia-Diarrhoea-report2016-web-version.pdf. [Last accessed on 2020 Mar 08].  Back to cited text no. 4
    
5.
Kelly M, Sandora T. Community acquired pneumonia. In: Kliegman R, Geme J, Blum N, Wilson K, editors. Nelson Textbook of Pediatrics. 20th ed. Philadelphia: Elsevier; 2019. p. 2266-74.  Back to cited text no. 5
    
6.
Jaiswal N, Singh M, Thumburu KK, Bharti B, Agarwal A, Kumar A, et al. Burden of invasive pneumococcal disease in children aged 1 month to 12 years living in South Asia: A systematic review. PLoS One 2014;9:e96282.  Back to cited text no. 6
    
7.
Cherian T, Mulholland EK, Carlin JB, Ostensen H, Amin R, de Campo M, et al. Standardized interpretation of paediatric chest radiographs for the diagnosis of pneumonia in epidemiological studies. Bull World Health Organ 2005;83:353-7.  Back to cited text no. 7
    
8.
Mathew JL, Singhi S, Ray P, Hagel E, Saghafian-Hedengren S, Bansal A, et al. Etiology of community acquired pneumonia among children in India: Prospective, cohort study. J Glob Health 2015;5:1-9.  Back to cited text no. 8
    
9.
Champatiray J, Satapathy J, Kashyap B, Mondal D. Clinico-aetiological study of severe and very severe pneumonia in two months to five years children in a tertiary health care centre in Odisha, India. J Clin Diagn Res 2017;11:SC06-10.  Back to cited text no. 9
    
10.
Chaudhary GS, Kumar S, Kankane A, Gupta S. Microbiological profile in community acquired pneumonia in children. Int J Pediatr Res 2018;5:263-7.  Back to cited text no. 10
    
11.
Kumar M, Badakali A, Mirji G, Vanaki RN, Pol R. Clinical profile and outcome of acute lower respiratory tract infection in children aged between 2 months to 5 years. Int J Contemp Pediatr 2016;4:105-11.  Back to cited text no. 11
    
12.
Jain S, Williams DJ, Arnold SR, Ampofo K, Bramley AM, Reed C, et al. Community-acquired pneumonia requiring hospitalization among U.S. children. N Engl J Med 2015;372:835-45.  Back to cited text no. 12
    
13.
Melegaro A, Edmunds WJ, Pebody R, Miller E, George R. The current burden of pneumococcal disease in England and Wales. J Infect 2006;52:37-48.  Back to cited text no. 13
    
14.
International Institute for Population Sciences (IIPS) and Macro International. National Family Health Survey (NFHS-4), 2015 – 2016 Uttarakhand Factsheet. Available from: http://rchiips.org/nfhs/pdf/NFHS4/UT_FactSheet.pdf. [Last accessed on 2019 Sep 29].  Back to cited text no. 14
    
15.
Yudhavir S, Pramod S, Singh A, Payal V. Bacteriological and Clinical Profile of Community Acquired Pneumonia in hospitalised children with associated co-morbidity in a tertiary care centre of Western Rajasthan, India. Int J Contemp Paediatr 2016;5:2320-7.  Back to cited text no. 15
    
16.
Tiewsoh K, Lodha R, Pandey RM, Broor S, Kalaivani M, Kabra SK. Factors determining the outcome of children hospitalized with severe pneumonia. BMC Pediatr 2009;9:15.  Back to cited text no. 16
    
17.
Lochindarat S, Teeratakulpisarn J, Warachit B, Chanta C, Thapa K, Gilbert GL, et al. Bacterial etiology of empyema thoracis and parapneumonic pleural effusion in Thai children aged less than 16 years. Southeast Asian J Trop Med Public Health 2014;45:442-54.  Back to cited text no. 17
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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