¹Assistant Professor, Department of Microbiology, Government Medical College, Nandurbar, Maharashtra, INDIA.

²Assistant Professor, ³Professor, Department of Microbiology, Lokmanya Tilak municipal Medical College Sion, Mumbai, Maharashtra, INDIA.

Email: ravidas.vasave.rv@gmail.com

RESULTS

In present study 250 children were studied. Majority of them were male (Most common risk factor in this study was daily massage with oils (94.8%). Other risk factors were trauma (79.6%), body piercing (19.2%) and previous hospitalization (14%). Heat 248 (99.2%), redness 246 (98.4%) and localized swelling 240 (96%) were the commonest clinical signs present.

Table 1: General-wise distribution

CRP was positive in 38 (15.2%) cases and negative in majority, i.e., 212 (84.8%) of the cases. The blood culture was positive in only 32 (12.8%) cases whereas in remaining 218 (87.2%) cases it was negative. Pus culture was positive in 145 (58%) cases and there was no growth in 105 (42%) samples. In one case (0.4%) acid fast bacilli were seen. Out of 152 infections in the cases of SSTIs in present study, 74 (48.68%) were gram positive and 78 (51.31%) were gram negative bacteria. Polymicrobial infection was noted in 4 cases.

Table 2: Laboratory findings

Out of 152 bacterial isolates, 59 (38.81%) were Staphylococcus aureus, 25 (16.44%) were Escherichia coli, 14 (9.21%) were Enterobacter spp. and 13 (8.55%) were Pseudomonas aeruginosa. Of the 74 gram positive organisms, 59 (79.72%) were Staphylococcus aureus, 5 (6.75%) were Streptococcus spp., 6 (8.13%) were Micrococci, 3 (4.05%) were Diphtheroids and one (1.35%) was Enterococcus spp Among all the gram negative organisms (n=78) isolated, Escherichia coli were the commonest (32.05%) followed by Enterobacter spp. (17.94%), Pseudomonas aeruginosa (16.66%), Klebsiella pneumoniae. and Acinetobacter spp. (14.10% each) and Citrobacter spp., Proteus mirabilis and Serratia spp. (1.28% each). The Micrococci and Diphtheroids were considered as commensals and not processed further.

Table 3: Frequency of Microorganisms isolated

All gram negative bacteria other than Pseudomonas aeruginosa and Acinetobacter spp. were sensitive to higher antibiotics such as colistin and tigecycline. Majority of the isolates were sensitive to meropenem (96.92%), amikacin (70.76%) and imipenem (63.07%). Amoxycillin-clavulanic acid (4.61%) and piperacillin (13.84%) were the least susceptible antibiotics.

Table 4: Antibiotic susceptibility pattern of Gram Negative organisms (n=65) (except Pseudomonas aeruginosa and Acinetobacter spp.)

Among the 13 isolates of Pseudomonas aeruginosa, 12 (92.30%) isolates were sensitive to imipenem. Higher antibiotics such as netilmycin and meropenem were susceptible to most of the strains (75% each).

Table 5: Antibiotic susceptibility pattern of Pseudomonas aeruginosa isolates(n=13)

All Acinetobacter spp. were sensitive to higher antibiotics such as imipenem, meropenem, colistin, tigecycline and netilmycin. Among other antibiotics the isolates were sensitive to piperacillin-tazobactam (63.63%) followed by ampicillin-sulbactam and cefepime (54.54% each). The isolates were resistant to amoxicillin-clavulanic acid, Cefotaxime, ceftazidime and co-trimoxazole. They were least sensitive to amikacin and ciprofloxacin (18.18% each).

Table 6: Antibiotic susceptibility pattern of Acinetobacter spp. isolates (n=11)

All the Staphylococcus aureus isolates were sensitive to higher antibiotics such as netilmycin, linezolid and vancomycin. Majority of the isolates were sensitive to clindamycin (83.05%) followed by gentamicin (76.27%), erythromycin (61.01%) and ciprofloxacin (44.06%).

Table 7: Antibiotic susceptibility pattern of Staphylococcus aureus isolates (n=59)

All the five isolates of Streptococcus spp. were susceptible to linezolid and vancomycin. Penicillin-G (20%), erythromycin (20%) and clindamycin (40%) were the least susceptible antibiotics.

Table 8: Antibiotic susceptibility pattern of Streptococcus spp.

DISCUSSION

Skin and soft tissue infections (SSTIs) are suppurative microbial invasions of the epidermis, dermis and subcutaneous tissues characterized by induration, erythema, warmth, and pain or tenderness. Local manifestations may be accompanied by systemic signs and symptoms, such as fever, chills, malaise and, at times, haemodynamic instability. Systemic signs include hypotension and associated findings consistent with severe sepsis/septic shock including mental obtundation, cardiovascular and/or pulmonary collapse among other organ system failures. Emergency department (ED) visits for skin and soft tissue infections in children have increased dramatically in the last decade.⁵ Accordingly, from 1997 to 2009, hospital admission for pediatric patients with skin and soft tissue infections increased from 1.9 to 3.4 million annually.⁶ During that same time, pediatric patients requiring incision and drainage have doubled. ⁶ This growing volume of patients is thought to be largely due to the emergence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). In the present study, majority of patients were male. In several other studies conducted by Ghadage DP et al.⁷ and Andrews RM et al.⁸ similar pattern of gender distribution was found. In present study most common risk factor was daily massage with oils (94.8%). Other risk factors were trauma (79.6%), body piercing (19.2%) and previous hospitalization (14%). None of the case had history of attending day care center, diabetes or presence of some other risk factor. Natural vegetable or plant oils (for example, mustard, sunflower, sesame, coconut, olive, and soybean oils) have emollient properties and in many low- and middle-income countries application of these to the newborn infant's whole body surface is a widespread traditional practice. ⁹ But, topical application of oils has not been shown to reduce the risk of infection or its associated morbidity or mortality, and may increase the risk of infection with coagulase-negative staphylococci in a study by Cleminson et al.⁹ Out of 156 cases, 152 (97.43%) were monomicrobial and 4 (2.56%) were polymicrobial infections. Among 152 monomicrobial infections, 74 (48.68%) were gram positive and 78 (51.31%) were gram negative bacteria. In a study by Rani et al.¹⁰ 90% cases yielded growth of bacteria, out of which 71.85% were monomicrobial and 28.14% were polymicrobial infections. Of the 152 bacterial isolates in present study, 59 (38.81%) were Staphylococcus aureus, 25 (16.44%) were Escherichia coli, 14 (9.21%) were Enterobacter spp. and 13 (8.55%) were Pseudomonas aeruginosa. Mohanty et al.¹¹ reported Staphylococcus aureus(38.05%), Escherichia coli(17.39%) and Pseudomonas aeruginosa(11.82%) as the top three isolates in their study. They have reported incidence of Enterobacter spp. as 2.80% in their study. Zargar et al.¹² from India and Rennie et al.¹³ and Sader et al.¹⁴ also reported these organisms among top five pathogens isolated from skin and soft tissue infections in hospitalized patients. In present study, resistance to methicillin was detected in 33 (55.93%) of Staphylococcus aureus isolates. MRSA is on the rise in SSTIs in children both in the hospital setup (HA-MRSA) and in the community. Prevalence of MRSA was found to be consistent with studies by Gupta et al.(54.5%)¹⁵,Anupurba et al.(54.8%)¹⁶ and by Roveta et al.(53%)¹⁷. All the Staphylococcus aureus isolates (n=59) were sensitive to higher antibiotics such as netilmycin, linezolid and vancomycin. Majority of the isolates were sensitive to clindamycin (83.05%) followed by gentamicin (76.27%), erythromycin (61.01%) and ciprofloxacin (44.06%), whereas, maximum resistance was seen to penicillin (95%). This is in correlation with the study of Thind et al.¹⁸ where Staphylococcus aureus showed 100% resistance to penicillin and 100% sensitivity to vancomycin, teicoplanin and linezolid. Ramana et al.¹⁹, Nagaraju et al.²⁰, Patil et al.²¹ and Singh et al.²² observed a similar high resistance of Staphylococcus aureus to penicillin. All gram negative bacteria other than Pseudomonas aeruginosa and Acinetobacter spp. were sensitive to higher antibiotics such as colistin and tigecycline. Majority of the isolates were sensitive to meropenem (96.92%), amikacin (70.76%) and imipenem (63.07%). Amoxycillin-clavulanic acid (4.61%) and piperacillin (13.84%) were the least susceptible antibiotics. Resistance of Gram negative organisms was minimum against meropenem, imipenem and amikacin which is similar to other studies.^23,24 The susceptibility data collected in this study suggests that the most common organisms likely to be encountered in soft tissue infections are gram-positive cocci, notably Staphylococcus aureus, many of them methicillin-resistant. Thus, any first line antibiotic treatment should be primarily directed against this pathogen. For coverage of gram negative bacteria, aminoglycosides, meropenem and imipenem would be more useful. Use of mono drug therapy with cephalosporins, aminoglycosides and fluoroquinolones need to be guided by the sensitivity report. Lastly, continued monitoring of susceptibility pattern need to be carried out in individual settings so as to detect the true burden of antibiotic resistance in organisms and prevent their further emergence by judicious use of drugs.

CONCLUSION

In present study the main pathogens involved in these infections are Staphylococcus aureus and gram negative enteric organisms. All the Staphylococcus aureus isolates were sensitive to higher antibiotics such as netilmycin, linezolide and vancomycin. Streptococcus spp. were susceptible to linezolide and vancomycin. All gram negative bacteria other than Pseudomonas aeruginosa and Acinetobacter spp. were sensitive to meropenem (96.92%), amikacin (70.76%) and imipenem (63.07%). Increasing antibacterial resistance is becoming a major problem in the treatment of these infections worldwide. Continued monitoring of susceptibility pattern need to be carried out in individual settings so as to detect the true burden of antibiotic resistance in organisms.

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