Minoru Ochiai

Gram-positive cocci are associated with the formation of completely pure cholesterol stones

OBJECTIVE:Recently it has been reported that bacterial DNA has been detected in mixed cholesterol stones (cholesterol content < 95%), which were not previously believed to be related to bacteria, using the polymerase chain reaction (PCR). We examined bacterial DNA in pure cholesterol stones to clarify the mechanism of initiation or promotion of the formation of cholesterol gallstones.METHODS:We examined 69 gallstones (30 brown pigment stones, 21 pure cholesterol stones, and 18 mixed cholesterol stones). Bacterial DNA was extracted from the core of the gallstones and amplified by PCR. Bacteria species in gallstones were identified by DNA sequencing of the PCR products.RESULTS:Bacterial DNA was detected in 26/30 brown pigment stones (87%), in 12/21 pure cholesterol stones (57%) (cholesterol content = 100%), and in 12/18 mixed cholesterol stones (67%) (cholesterol content = 82–95%). Bacterial species in gallstones were identified by DNA sequencing of PCR products. Eighty percent of bacteria in brown pigment stones were gram-negative rods or anaerobes. In contrast, 100% of bacteria in pure cholesterol stones were gram-positive cocci. The bacteria in mixed cholesterol stones consisted of 40% gram-positive cocci, 50% gram-negative rods, and 10% anaerobes.CONCLUSIONS:It was strongly suggested that gram-positive cocci are associated with the formation of pure cholesterol stones.

Rectal obstruction by a giant pharmacobezoar composed of magnesium oxide: Report of a case

This report presents the rare case of a 75-year-old woman who developed a rectal obstruction caused by a pharmacobezoar, following the long-term ingestion of magnesium oxide cathartics for constipation. She was admitted to the hospital with lower abdominal pain and nausea. Abdominal computed tomography and magnetic resonance imaging showed that a huge calcified mass caused the rectal obstruction. A divided sigmoid colostomy was performed to relieve her symptoms, a colonoscopy from the distal stoma delineated a huge bezoar in the rectum, and thereafter she underwent an enterotomy. Magnesium oxide was detected in an analysis of a sample from this bezoar. Phamacobezoars resulting from laxatives or cathartics have rarely been reported. The current report showed a rectal obstruction caused by a pharmacobezoar composed primarily of magnesium oxide.

Diagnostic Significance of Serum CEA and CA19-9 Levels in Colorectal Cancers

We investigated the clinical significance of measuring serum CEA and CA19-9 levels for the early diagnosis of colorectal cancer in 157 cases. In the present study, the preoperative positive rate of serum CEA and CA19-9 levels in patients with curatively resected primary cancer was only 14.5% (11/76), 12.1% (4/33) of Dukes A, B, and 22.0% (11/50), 27.6% (8/29) of Dukes C, respectively, however, we found that serum CEA or CA19-9 levels were positive in 82.4% (14 cases) of 17 recurrent colorectal cancers after curative resection and that the elevation of these tumor markers was the first diagnostic method of recurrence in 38.1% of 21 cases. Thus, we conclude that the measurement of serum CEA and CA19-9 levels is not useful for the diagnosis of primary colorectal cancers, but is very useful for the early detection of recurrent colorectal cancers.

A Clinicopathological Study of Surgically Treated Colorectal Cancer

One hundred ninety three patients with colorectal cancer surgically treated at our department were reviewed from 1987 to 1992. The age of patients receiving surgical treatment ranged 33 to 86 years, with an average of 61.6 years. Location of colorectal cancers was as the following, rectum; 76 (39.4%), sigmoid colon; 56 (29.0%), descending colon; 10 (5.2%), transverse colon; 12 (6.2%), ascending colon; 23 (11.9%), cecum; 16 (8.3%). Curative operations were performed for 152 cases (78.8%). Thirty two cases (16.6%) were done with noncurative operations. Non-curative operations were performed more frequently for right-sided colon cancers than for left-sided colon and rectal cancers. Patients of Dukes’ A, B and C were 77 (39.9%), 24 (12.4%) and 92 (47.7%) cases. Furthermore, lesions of Dukes’ A and B cancers were found more frequently in left-sided colon and rectal than in right-sided colon. Thus, it is important for the total colonoscopy to be done for not only symptomatic but also asymptomatic patients because of the discovery of early or curative colorectal cancers, especially right-sided colon cancers.