Estimation of average bioburden values on flexible gastrointestinal endoscopes after clinical use and cleaning: Assessment of the efficiency of cleaning processes

Peer review under responsibility of Alexandria University Faculty of Medicine.

Available online 21 June 2014

Figures & data

Table 7 Number and percentage of HCV.

HCV	Number	Percent (%)
Positive	15	12.5
Negative	105	87.5
Total	120	100

Table 8 Bioburden distribution (cfu/ml) on flexible gastroduodenoscopes immediately after use and before pre-cleaning in surgical department endoscopy unit.

Cases	After use in surgery endoscopy unit
	Aerobe	Anaerobe	Total
Average	1.42 × 10^6	1.34 × 10^6	2.76 × 10^6

Table 1 Number and types of endoscopes used in the study.

Dept. & type of endoscope	After use	After cleaning	After HLD	Total
Surgery endoscopy unit
Gasteroduodenoscopy	17	16	19	52
Colonoscopy	3	4	1	8
Internal medicine endoscopy unit
Gasteroduodenoscopy	15	16	16	47
Colonoscopy	5	4	4	13
Total				120

Table 2 Number and percentage of sex distribution.

Sex	Number	Percentage (%)
Male	96	80
Female	24	20
Total	120	100

Table 3 The age distribution of the studied cases.

Age	Number	Percentage (%)
20–29	2	1.7
30–39	6	5
40–49	27	22.5
50–59	45	37.5
60–69	26	21.7
70–79	14	11.6
Total	120	100

Table 4 Number and percentage of the main patients complains.

Main complain	Number	Percentage (%)
Pain or discomfort in the upper abdomen	51	42.5
Repeated vomiting	20	16.7
Epigastric pain	13	10.8
Hematemesis	10	8.3
Melena	8	6.7
Unexplained changes in bowel habit	7	5.8
Constipation	6	5
Dysphagia	5	4.2
Total	120	100

Table 5 The final diagnosis of the studied cases.

Diagnosis	Number	Percentage (%)
Gastroduodenitis	48	40
GERD	13	10.8
Esophageal varices	18	15
Peptic ulcer	20	16.7
Cancer	15	12.5
Normal	6	5
Total	120	100

Table 6 Result of Helicobacter pylori testing.

H. pylori	Number	Percentage (%)
Positive	18	18
Negative	81	82
Total	99	100

Table 10 Bioburden distribution (cfu/ml) on flexible gastroduodenoscopes immediately after use and before pre-cleaning in internal medicine endoscopy unit.

Cases	After use in internal medicine endoscopy unit
	Aerobe	Anaerobe	Total
Average	8.82 × 10^6	9.90 × 10^6	1.87 × 10^7

Table 12 Bioburden distribution (cfu/ml) on flexible gastroduodenoscopes after cleaning in surgical department endoscopy unit.

Cases	After cleaning in surgery endoscopy unit
	Aerobe	Anaerobe	Total
Average	2.74 × 10^2	2.51 × 10^2	4.74 × 10^2

Table 13 Bioburden distribution (cfu/ml) on flexible colonoscopes after cleaning in surgical department endoscopy unit.

Cases	After cleaning in surgery endoscopy unit
	Aerobe	Anaerobe	Total
Average	5.56 × 10^2	4.80 × 10^2	1.04 × 10^3

Table 14 Bioburden distribution (cfu/ml) on flexible gastroduodenoscopes after cleaning in internal medicine endoscopy unit.

Cases	After Cleaning in internal medicine endoscopy unit
	Aerobe	Anaerobe	Total
Average	1.83 × 10^2	1.24 × 10^2	3.14 × 10^2

Table 15 Bioburden distribution (cfu/ml) on flexible colonoscopes after cleaning in internal medicine endoscopy unit.

Cases	After cleaning in internal medicine endoscopy unit
	Aerobe	Anaerobe	Total
Average	4.41 × 10^2	3.60 × 10^2	7.26 × 10^2

Table 16 Summary of gastroduodenoscope bioburden immediately after use and after cleaning (Surgical department endoscopy unit).

Location	Range		Mean
	cfu in channel	cfu on surface	cfu in channel	cfu on surface
Immediately after use	6.1 × 10^4–5.7 × 10^7	3.4 × 10^5–3 × 10^7	7.60 × 10^6	6.74 × 10^6
After cleaning	2.1 × 10^2–3.5 × 10^3	2.8 × 10^2–3.4 × 10^3	5.98 × 10^2	5.67 × 10^2

Table 17 Summary of gastroduodenoscope bioburden immediately after use and after cleaning (internal medicine endoscopy unit).

Location	Range		Mean
	cfu in channel	cfu on surface	cfu in channel	cfu on surface
Immediately after use	1.4 × 10^5–3.7 × 10^8	6 × 10^4–6.6 × 10^7	4.40 × 10^7	1.15 × 10^7
After cleaning	2.5 × 10^2–3 × 10^3	2.6 × 10^2–4.2 × 10^2	4.81 × 10^2	3.12 × 10^2

Table 9 Bioburden distribution (cfu/ml) on flexible colonoscopes immediately after use and before pre-cleaning in surgical department endoscopy unit.

Cases	After use in surgery endoscopy unit
	Aerobe	Anaerobe	Total
Average	1.51 × 10^7	1.70 × 10^7	3.21 × 10^7

Table 11 Bioburden distribution (cfu/ml) on flexible colonoscopies immediately after use and before pre-cleaning in internal medicine endoscopy unit.

Cases	After use in internal medicine endoscopy unit
	Aerobe	Anaerobe	Total
Average	2.82 × 10^7	2.67 × 10^7	5.49 × 10^7

Table 18 Comparison between the 2 endoscopy units as regarding the range of bioburden distribution immediately after use.

Units	Range of CFU on endoscopes	Mean
Surgery	(5.01 × 10^5–8.7 × 10^7)	3.49 × 10^7
Internal medicine	(4.97 × 10^5–3.7 × 10^8)	7.6 × 10^7

Table 19 Comparison between the 2 endoscopy units as regards the range of bioburden distribution after cleaning.

Units	Range of CFU on endoscopes	Mean
Surgery	(5.1 × 10^2–6.5 × 10^3)	1.06 × 10^3
Internal medicine	(5.2 × 10^2–3.42 × 10^3)	1.04 × 10^3

Table 20 Summary of reduction of bioburden after manual cleaning and after sterilization.

Location	CFU on endoscopy	Mean
Pre-cleaning	4.97 × 10^5–3.7 × 10^8	3.7 × 10^7
After manual cleaning	5.1 × 10^2–3.42 × 10^3	1.0 × 10^3
After sterilization	0	0

Table 21 Frequent and percentage of microorganisms isolated immediately after use (pre-cleaning).

Microorganism	Frequent of isolation	Percentage (%)
Staphylococcus	80	100
Streptococcus	72	90
Klebsiella	26	32.5
E. coli	16	20
Bacteroides	10	12.5

Table 22 Frequent and percentage of microorganisms isolated after manual cleaning.

Microorganism	Frequent of isolation	Percentage (%)
Staphylococcus	80	100
Streptococcus	80	100
Pseudomonas	35	43.3
Klebsiella	22	27.5
E.coli	8	10
Bacteroides	5	6.3