Proportion of bacteria causing healthcare associated infection in Khartoum orth Teaching Hospital

Background: This study was conducted at Khartoum North Teaching Hospital (KNTH) in the period between June 2005 to September 2007 in order to determine the bacteria that causes common healthcare associated infection (HAI.) Methods: Hundred bacteriological specimens from patients with HAI from different surgical and internal medicine departments (27 from patients in obstetrics and gynecology units, 33 from patients in surgical ward, and 16 from urology units, 12 from the medicine, 8 from the otorhinolaryngyology and 4 from ophthalmology departments) were collected. All samples were cultured on suitable bacterial culture media and processed. Presence of significant growth was further studied to identify type of pathogen and its susceptibility against selected (common used) antibiotics. Results: Study showed that the most frequent bacteria isolated from patients as a cause of HAI were Pseudomonas aeruginosa (23%) , Proteus mirabilis (17%) , and E. coli (13%) respectively. Conclusion: The study also revealed that all Gram-negative isolates were highly sensitive to antibiotic such as ceftriaxone, ciprofloxacin and imipenem, while P aeruginosa showed resistant to many commonly used antibiotics, but was sensitive to imipenem and pipracillin. All Gram-positive isolates were sensitive to vancomycin. Further studies are needed to evaluate the common microorganisms causing HAI and their drug susceptibility and proportion of HAI in this setting.


ospitals
and clinics were recognized as sources of infection long before the recognitions of microorganisms as causative agents of diseases1.Nosocomial or healthcare associated infection (HAI) has been a persistent major problem in every institution where patient care is provided.Worldwide, millions of patients develop such infection, resulting in several thousands of deaths and an economic cost of several billions dollars [1][2][3] .
1.Alzaiem Alazhari University, Faculty of Medical Laboratory Sciences 2.Alzaiem Alazhari University, Faculty of Medicine Correspondent: Abdullahi N Hassan.E-mail: Abdullahi2001@yahoo.com HAI is a problem which limited neither to developed nor to developing countries .However, the problem is likely to be greater in the latter [1][2][3][4] .Bacterial infection is a common cause HAI 5 .Also most bacterial infection can be easily diagnosed and treated with few exceptions.But nowadays the emergence and spread of resistance bacteria (especially Enterobacteriaceae) are complicating the treatment of serious HAI and threatening to create species resistant to all currently available agents [3][4][5][6] .
The aim of this study was to identify the common bacterial agent causing HAI in Khartoum North Teaching Hospital (KNTH) and their antibiotic susceptibility.were reported to the patients and their doctors.

Results
Hundred bacteriological samples from the patients were collected and processed.Bacterial growth was seen in 74 of collected samples, with different bacteria isolates as shown in Table 1.All Gram-negative isolates were highly sensitive to antibiotic such as ceftriaxone, ciprofloxacin and imipenem, while P aeruginosa showed resistant to many commonly used antibiotics, but was highly sensitive to imipenem and pipracillin as shown Table 2.All Gram-positive isolates were sensitive to vancomycin, while all isolated enterococci were resistant to gentamicin.Table3.Gram-negative bacteria accounted for more than two third of isolates.Similar results were reported from different studies done in developed and undeveloped countries [5][6][7] .
Gram-negatives such as E coli, P aeruginosa, P mirabilis, K pneumonia and S aureus were most common causative agents in patients with nosocomial UTI in this study.Different results were obtained from studies done in European countries which showed low proportion of the microorganism in urine than this study, except P aeruginosa which showed higher proportion than our study [7][8] .
The most common bacteria causing nosocomial wound infections in this study were P mirabilis, P aeruginosa followed by S aureus and other Gram-negative bacteria.Studies done in India showed that Pseudomonas aeruginosa (51.5%) was the commonest pathogen followed by Staphylococcus aureus (11.15%),Klebsiella Pneumonia (9.23%) and Proteus mirabilis (2.3%) 9 .K pneumonia, P aeruginosa and S aureus were isolated from lower respiratory tract infection in this study.Similar results were obtained from study done by Kofteridis et.al 10 .Studies from Southern Taiwan showed that the most frequently bacteria isolated from ear were Streptococcus pneumonia ( 21.8%), followed by Haemophilus Influenzae (10.2%),Staphylococcus aureus ( 7%) and Pseudomonas aeruginosa (1.8 %) 11 , while Marton et al showed that Streptococcus pneumonia was the most common bacteria causing ear infection 12 .
Antibiotic resistance is serious and growing health problem, gaining international and national attention as resistance increases at an alarming rate in both hospital and physician practice setting [13][14][15] .In this study, most of Gram-negative bacteria were sensitive to the imipenem and ciprofloxacin.However, gentamicin resistance was seen among Pseudomonas aeruginosa.E.coli resistant to ciprofloxacin were isolated from the urine elsewhere 13 .Gadapalli et.al in their study showed pipracillin resistance among Pseudomonas aeruginosa isolated from diabetic wound 9 .In this study Pseudomonas aeruginosa (86%) was sensitive to the pipracillin.
Many studies revealed increasing multi drug resistant (MDR) Gram-negative and Gram-positive bacteria in most of the hospitals settings [14][15][16][17][18] .Studies also showed increasing number of patients infected with vancomycin resistance Enterococcus and vancomycin intermediate sensitive Staphylococcus aureus [18][19] .But no vancomycin resistance was observed among all Gram-positive isolates.Also some microorganisms showed resistance to many commonly used drugs.

Conclusion:
This study concluded that the high percentage of bacteria causing HAI have more or less similar drug sensitivity to other countries.However, highly resistant Gram-negative bacteria such as P aeruginosa were also seen.

Table 1 :
demonstrates relation between samples and results of isolations.

Table 2 :
Susceptibility test for Gram-negative bacteria

Table 3 :
Susceptibility test for Gram-positive bacteria