The geography of chronic digestive disease in southern Africa

Lifestyle and dietary patterns are in the process of rapid transformation in Soweto. Comparisons with whites indicate differences in bowel behaviour, lactase deficiency and breath methanes. The association between smoking pipe tobacco and cancer of the oesophagus is confirmed, but home-brew consumption has been found to be the major risk factor in this cancer. A recent swing to Western-type alcohol has led to the emergence of alcohol-induced pancreatitis in blacks. Urbanisation and westernisation have also affected the influence of the traditional healer and the incidence of duodenal ulcer disease. The fundamental environmental influence which determines non-infective large-bowel disease is diet. A dietary survey of Sowetans indicates that their present diet is low in fat and fibre. Despite the latter, appendicitis is still relatively uncommon. Other significant differences are observed in colorectal cancer and diverticular disease.

Colorectal cancer. Some aspects of epidemiology, risk factors, treatment, screening and survival

In developed populations colorectal cancer, which after lung cancer is the commonest of cancers, accounts for up to 6% of all deaths. It occurs most frequently in populations in prosperous industrialised countries, save Japan, and is rare in Third-World populations pursuing a traditional lifestyle. Peak occurrence is in the 7th decade. Colon cancer affects the sexes equally, but males are much more prone to rectal cancer. The precise causation is uncertain. Risk factors include genetic or familial predisposition, inflammatory bowel disease, diet (especially high fat and low dietary fibre intakes), and possibly alcohol intake. Surgery remains the treatment of choice. Stage is by far the most important factor influencing prognosis. Major refinements in both surgical and therapeutic measures have had disappointingly little effect on survival time. Overall median mortality occurs in 1-1 1/2 years; only one-third to one-half of patients survive for 5 years. While effective screening for very early detection could increase survival time, this will result only from further education. Since little avoiding action is practicable, the outlook for patients will remain daunting until help is sought far earlier.

Breath methane and large bowel cancer risk in contrasting African populations

Breath methane has been measured in 1016 people from four populations resident in Southern Africa which experience widely different risks of bowel cancer and other colonic diseases. Highly significant differences in the proportion of subjects with detectable methane in breath were found; % producers--rural black 84, urban black 72, white 52, Indian 41 (chi 2 121 p less than 0.001 3 df). There was a slight preponderance of female producers over male (female producers 63%, males 57%) and an age trend with fewer producers in the older age groups in the urban blacks and Indians, these comparisons being significant when tested by stepwise logistic regression analysis. Bowel cancer risk, determined from a variety of sources, was lowest in rural blacks, greatest in whites, with intermediate rates for urban blacks and Indians. Methane production in the human colon shows significant interethnic differences but which bear no relation to bowel cancer risk in these populations.

Primary lymphoma of the small bowel with obstructive jaundice and pancreatitis. A case report

Primary lymphoma of the small bowel resulting in pancreatic duct or biliary obstruction is rare. Only 1 case of pancreatic obstruction causing pancreatitis has previously been reported. A patient with primary small-bowel lymphoma of the 'Western' variety is described. This was associated with extensive duodenal involvement and obstruction of the pancreatic and biliary system accompanied by obstructive jaundice and pancreatitis.

Salivary immunoglobulins in healthy white and black adults compared with oesophageal cancer patients

Saliva is a readily accessible mucosal secretion and salivary antibodies reflect the repertoire of gut-associated antigens; it therefore appears to be ideal for the study of gastro-intestinal disease. A study of salivary immunoglobulins in healthy white and black adults and patients with oesophageal cancer showed that salivary immunoglobulin A levels were higher (but not significantly) in whites than blacks. The levels, however, were similar in healthy blacks and oesophageal cancer patients. There is a wide variation in normal levels of salivary immunoglobulins. Also, immunoglobulins are readily influenced by physiological factors and so at present are unreliable indices of gastro-intestinal disease.

Characteristics and occurrence of appendicitis in the black population in Johannesburg, South Africa

In black patients seen at Baragwanath Hospital, Johannesburg, appendicitis occurs most frequently in the 10-19-year-old age group. There is a pronounced male bias. Parasitic ova in the appendix are very seldom observed (3.6%). Fecaliths, present in 20% of diseased appendices, are noted far less frequently than are reported for white patients (50%-75%). There are about two cases of appendicitis per 1,000 admissions of adults annually, a low frequency consistent with the tenfold differential of appendectomies reported to prevail in urban black and white adolescents. The progressively changing diet of urban blacks, currently low in fat and in dietary fiber, has not yet become associated with a marked increase in the occurrence of the disease (nor of most other noninfective bowel diseases).

Rectal manifestations of pellagra

Twenty (44%) of 45 patients with cutaneous pellagra had diarrhoea. Inflammation was seen on sigmoidoscopy in 42 and was severe in 5 (11%), moderate in 4 (9%) and mild in 33 (73%). Six patients (13%) had perianal excoriation. Rectal biopsies taken in all cases showed extensive ulceration in 1 case, moderate to severe inflammation in 16 (36%) and mild inflammation in 18 (40%). Minimal oedema of the lamina propria was seen in 11 (24%) patients. At 5 to 7 days after starting vitamin treatment in nine cases histological changes had returned to normal in 4, improved in 3 and had not changed in 2. Diarrhoea stopped within a week in all cases.

Obstructive jaundice in the South African black population

We report the causes of obstructive jaundice in 56 black South African patients. Chronic pancreatitis and malignant biliary obstruction occurred with equal frequency. These two conditions may be difficult to differentiate clinically and radiologically, and only operative pancreatic biopsy may be diagnostic. Choledocholithiasis caused jaundice in only 7.1% of the patients, reflecting the relatively low prevalence of gallstones in this population.

Chronic digestive disease in an urban black population

There is a marked contrast in incidence of chronic digestive diseases between black populations of sub-Saharan Africa and Western populations. Environmental factors inherent in modern Western civilization have been incriminated as largely responsible for the differences observed. The significance of these factors in chronic digestive disease in Soweto is emphasized since they provide clues to aetiology. In this context research avenues with regard to specific diseases are suggested.

Esophagitis in a population at risk for esophageal carcinoma

A previously unreported high incidence of endoscopically identifiable, diffuse, largely nonulcerative esophagitis, is described in a selected population of Southern African blacks at risk of cancer of the esophagus. This is comparable with findings in similar groups in Iran and China. The incidence of dysplasia and "early" cancer is still undefined in South Africa.

Further observations on social factors associated with duodenal ulcer in Soweto

It has been postulated that urbanisation is an important factor in the genesis of duodenal ulcer. This study of 100 duodenal ulcer patients, and 100 hospital controls, matched according to sex, age, education and occupation, and an additional 50 unmatched endoscopically negative controls, confirmed that duodenal ulcer patients were mainly young men who were more likely to have been born in an urban area than the controls. Furthermore, a significant number of duodenal ulcer patients were born and reared in the smaller towns of South Africa and then moved to Soweto. It is suggested that frustrated aspirations in these towns might even be greater than in Soweto. In the context of the Soweto population where occupational and educational status is generally low, duodenal ulcer patients were of a higher educational and occupational category than Sowetans and unselected controls. Thus factors associated with urbanisation such as education and occupation and the pattern of urbanisation play key roles in duodenal ulcer. Investigation into particular aspects of the work situation such as the degree of autonomy exercised at work, authority over others and attitudes to supervision yielded no significant results.

Survival of black men with prostatic cancer in Soweto, Johannesburg, South Africa

While prostatic cancer has a low frequency in rural African black men living traditionally, the disease occurs more often and is increasing in black men in the cities. Between 1982 and 1984, 101 patients with prostatic cancer were detected in Soweto, Johannesburg. Of these patients 90 had clinical stage D disease and metastasis was common. The 50 per cent mortality period of 1.6 years, while similar to that reported in some series of white patients, is considerably shorter than that noted in several others series.

Low survival of South African urban black women with cervical cancer

In Soweto, Johannesburg, the incidence of cervical cancer, the most common cancer in black women, is higher than in most white populations but lower than in many other populations. In a series of 210 patients who were diagnosed in 1981 and 1982, 50% had died within 1.6 years of diagnosis, a third of the reported survival time in white patients. The pattern of stage at presentation was similar to, although sometimes later than, those reported for various white communities. Data on patients' age at birth of first child, parity, smoking practice, and socioeconomic status, differed little from those in a control group. Neither these factors, nor availability of medical services, could be correlated with the distressingly short period of survival, which also occurs among urban black patients with breast and oesophageal cancers. Presumably, unidentified factors linked with low socioeconomic status affect survival time.

Bowel function in an urban black African population

Despite a low daily dietary fiber intake, an urbanized black African population in southern Africa has a low incidence of those diseases associated with fiber deficiency. Stool weights, defecation frequencies, and transit times in this group are much closer to those of westernized whites than to rural blacks.

The liver in biliary obstruction due to chronic pancreatitis

Biliary obstruction is an important complication of chronic calcifying pancreatitis. In this study, liver biopsies were examined to determine the nature and severity of hepatic complications in 23 such cases. The most striking changes were portal tract expansion due to oedema and fibrosis, with proliferation of bile ducts. Although common, these changes were not severe, and no patient had developed secondary biliary cirrhosis. Other features of note were intrahepatic cholestasis, iron overload (56.5%), copper-associated protein stained with the orcein technique (34.7%) and mild fatty change or perivenular sclerosis in 13%. It is concluded that no serious, irreversible pathological changes occurred in the liver despite clinically marked biliary obstruction.

Benign extrinsic oesophageal dysphagia. Case reports

Six patients with benign extrinsic oesophageal dysphagia are presented, 4 with dysphagia aortica and 1 each with dysphagia due to cervical osteophytes and traction diverticulum. The radiological features of these cases are discussed. It is emphasized that such cases form a small but significant entity.

Bile obstruction in hepatocellular carcinoma--visualization by endoscopic retrograde cholangiography. A case report

Extrahepatic biliary obstruction is a rare presentation in hepatocellular carcinoma (HCC), only 31 cases having been reported in the literature. We describe a patient with extrahepatic biliary obstruction in whom endoscopic retrograde cholangiography was suggestive of cholangiocarcinoma. Laparotomy and subsequent investigation, however, confirmed HCC metastasizing to the common hepatic duct. The cholangiographic appearance of HCC involving extrahepatic bile ducts is emphasized and features differentiating it from cholangiocarcinoma are highlighted. Even though extrahepatic biliary obstruction in HCC is rare, this disorder should be considered in the differential diagnosis of obstructive biliary tract disease.

Short duration of survival among South African blacks with oesophageal cancer

South African urban Blacks are very prone to oesophageal cancer, and mean age at diagnosis is almost a decade lower than that of White patients (male preponderance is equally marked in both ethnic groups). In recent years the socio-economic position of urban Blacks has improved greatly, with considerable strides being made in literacy and awareness of hospital services. This socio-economic improvement could conceivably improve the extremely short durations of survival among oesophageal cancer patients noted in earlier studies; this, however, has not occurred. Of a series comprising 146 male and 37 female patients, 50% had died after 3,6 and 4,2 months respectively. The corresponding periods noted for White patients are about twice as long.