Small bowel volvulus is a rare cause of small bowel obstruction in the western and the USA [1, 2, 8]. The incidence rate of SBV is high (24-60 per 100,000populations) in Africa, Asia and Middle Eastern while low (1.7-5.7 per 100,000populations) in western [6]. Annual occurrence in the USA and Europe is quite low compared with that in Africa, Middle East countries, and Asian [2-3, 7, 13-15] (Table1). A 57-years data review in the USA found that annual occurrences of SBV was 0.6case per year and SBV accounted for 6.9% of all bowel obstruction [7]. Welch CE 1958 reported that the prevalence reduction from 6.9% to 3.3% in the period of 1930-1958 in the USA [16] .A. Roggo and L. W. Ottinger (1992) at the Massachusetts General Hospital over 10 years reported those 35 small bowel volvulus were treated which represented 1.7% of bowel obstructions and 4% of small bowel obstructions [7]. Vaez-Zadeh et al (1969) reported the incidence of small bowel volvulus in Iran was 19.6% and 41% in bowel obstruction and small bowel obstruction respectively [2].
Table 1: Literature Review
Authors
|
Atalel F.
Current study
|
M. Demssie
|
Roggo
|
Frazee
|
Welchi
|
Veaz-Zadah
|
Study Place
|
DGH, Ethiopia
|
Southern,
Ethiopia
|
Bosten
|
Rochester MN
|
Glasgow
UK
|
Iran
|
Study period
|
Jan1,2016-Dec31, 2019
|
June 1992toMay 1996
|
1980-1990
|
1975-1984
|
1965-1980
|
1962-1965
|
Duration Years
|
4
|
4
|
10
|
10
|
15
|
5
|
No of patients
|
148
|
98
|
35
|
57
|
53
|
41
|
Annual occurs
|
37
|
24.5
|
3.5
|
5.7
|
3.5
|
8.2
|
Male to Female
|
5.4:1
|
8.8:1
|
1:1.2
|
1:1
|
1:1.12
|
9.25:1
|
Mean age
|
41.14
|
34.1
|
67
|
59
|
54
|
42
|
Primary SBV(%
|
100
|
94.9
|
14
|
11
|
30
|
80
|
Secondary SBV(*%
|
0
|
5.1
|
86
|
89
|
70
|
20
|
Gangrenous SBV(%
|
16.9
|
28.7
|
46
|
49
|
43
|
-
|
Overall Mortality
|
3.4
|
13.3
|
9
|
12
|
28
|
15
|
Viable SBV
|
2.4
|
8.3
|
0
|
3
|
11
|
-
|
Gangrenous SBV
|
8
|
25.9
|
17
|
21
|
47
|
-
|
A series of research done in Ethiopia reported that small bowel volvulus accounted sizable portion of bowel obstruction; Tegegne A. 1992(18.3%) [9], Lintjorn B.1981et al (38.6%) [10], M. Demissie 2001(41.7%) [2], Gizaw TA.et al 2016, (36.4%) [11], Soressa U.et al 2016, (30.3%) [12]. I.O.McDonald et al. 1980 reported more than 50% of bowel obstruction due to Small bowel volvulus in Nepal [5]. This great discrepancy of the prevalence of small bowel volvulus may due to dietary factors that when a bulky bolus of food entered the proximal jejunum, that loop felt down into pelvis and causing empty distal bowel to rise into a right upper quadrant. Rapid emptying of the stomach and diaphragm makes the distal bowel spread across the left upper quadrant. As this distal loop themselves filed up would fall into left quadrat completing 3600 twists [3]. Primary SBV is more common in developing countries while secondary SBV is more in developed countries. Frazee RC et.al 1988 (UK) and A.Roggo and L. W. Ottinger 1992(USA) noted that secondary SBV accounted for 89%&86% of SBV respectively [13, 7](Table1). A Research done by Vaez-Zadeh et al 1969(Iran), M.Demssie 2001(Ethiopia) and De Souza LJ1976 (Uganda) showed that primary SBV accounted 80%, 94.9% and 100% of SBV respectively [2, 3, 15] (Table1).We found that primary SBV accounted 100% of SBV. The presumed risk factors in different literature were hypermobility of bowel gut, hypermobility of mesentery, and bulky and poorly digestible diet taken at long intervals [2, 7, 13,17].
The speculation was some populations have long mesenteric and short roots of mesentery which would allow abnormal mobility of whole or segment of the small bowel. Diet and pattern of feeding is also the most relevant risk factor for occurrences of primary SBV. The Abrupt change of dietary habit of ingestion of a single large amount and bulky food after a long interval of fasting or empty of bowel may induce forceful bowel peristalsis, resulting in SBV [2, 7,13,17]. Secondary small bowel volvulus occurs in the presence of underlying identified predisposed conditions. It is mainly seen in bands, post-op adhesion, malrotation, or midgut nonrotation in newborn and young children and a gastrointestinal infestation of the parasite. The prevalence of secondary SBV is more common in western, constituting a 70-90 %of case [7].
The prevalence of primary SBV is more common in children and young while secondary SBV is dominantly in old age. A study conducted in the different areas stated that the mean age was 67 years in the USA ,34 years in Ethiopia, 42 years in Iran,59 years in the UK(2,3,7,13](Table1). We found that the mean age was 42 years. The incidence of SBV is a male predominance, particularly in developing countries. The research described that male to female proportion 1:1.2 in USA, 1:1.12 in UK, 9.25:1 in Iran, 8.8:1 in Ethiopia [2, 3, 7, 13]. We found similar results on the male to female proportion 5.4:1(Table 1). The exact cause of sex discrepancy is not well-illustrated but possible reasons suggested that spacious female pelvic area allowed a greater possibility of spontaneous reduction of volvulus, females have a lax abdominal wall due to childbearing, doing less heavy and prolonged exercise and more obese [2, 3, 7].Our finding noted that SBV was more common in rural resident due to more childbearing, doing less heavy, long time fasting and higher fiber diet.
The literature review summarized the common complaints of SBV abdominal pain 94-100%, vomiting 83-100%, and abdominal distention 55-100% [7]. Our result identified the common clinical complaints of SBV similar to the previous review; abdominal pain 98%, vomiting 92.1 % and distention 61.5% and frequent physical findings were abdominal tenderness 85.1% and visible peristalsis 64.9%.
SBV has been contributing a significant burden in mortality and morbidity especially when the bowel becomes gangrenous, ischemic, and develops peritonitis. The prevalence of gangrenous SBV depends on the health-seeking behavior of the community, access to a health facility, early diagnosis, and economy of the patients. The incidence of gangrenous SBV was 28.7 in Ethiopia, 46 % in the USA, and 43% in the UK [2, 7, 13].
Our study found that the incidence of gangrenous SBV 16.9%. This difference study conducted in the USA and UK was in the early 1950s and currently increases access to surgical investigation modality decreasing the incidence of gangrenous SBV.
SBV had a high mortality rate but currently mortality due to SBV decreasing due to the advance of surgical health, investigation, and early diagnosis. Overall mortality rate reported 26% in Nepal ,13.3% in Ethiopia,28% in UK,9 % in USA and 15% in Iran[2,3,5,7,13].Our finding was lowered compared with the previous study (3.4%).