Brief Answer:
see a doctor as soon as possible

Detailed Answer:
Hello,
Dark stools and blood in the stools may indicate a serious problem like colon cancer. You really need to see a doctor and get a colonoscopy done as soon as possible. It can also be from something more benign like hemorrhoids but you need to make sure that it is not something more serious.
Severe constipation or inflammation in the colon can also cause bleeding and back pain but in any case you need a definite diagnosis before you can get proper treatment.
In the mean time. Drink plenty of fluids and do not let yourself get constipated.
Regards,
Dr. Robinson

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Brief Answer:
not likely gallbladder or kidneys

Detailed Answer:
While the gallbladder and kidneys may cause back pain if there is a problem in one of those areas, it would not cause blood in the stools. Gallbladder issues may cause green stools but not dark or with blood. Kidney disease does not cause changes in the stools.
If you had a colonoscopy with no precancerous polyps 5 years ago then that makes colon cancer very unlikely. It could be another problem in the colon like inflammatory bowel disease or diverticulitis.
Even though colon cancer is less likely in your case it would still be a good idea to see a doctor for an exam and a determination if another colonoscopy is needed. I hope you feel better soon.
Regards,
Dr. Robinson




Brief Answer:
see above

Detailed Answer:
Please see my reply to this question above.
Dr. Robinson

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