Mehl. colorectal part table Flashcards
most common causes of rectal bleeding?
Diverticular bleed is most common cause of painless bleeding per rectum in elderly, followed by colorectal cancer, followed by angiodysplasia.
Diverticulosis. Can cause colovesical fistula.
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Diverticulosis. Do not confuse with diverticulitis, which is when a diverticulum becomes inflamed.
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Diverticulitis CP?
LLQ pain + fever in patient over 60. Very HY.
Inflamed diverticulum, usually in the sigmoid colon.
Diverticulitis. Dx?
CT of the abdomen with contrast is how to diagnose.
Diverticulitis. what NOT TO DO in ACUTE?
Endoscopy ==> perofration
Diverticulitis. You give Abs => follow up?
After patient is treated with antibiotics, a colonoscopy should be scheduled weeks to months later to rule out malignancy. But once again, never scope acutely.
Diverticulitis. If perforation, tx?
Perforated diverticulitis can require colectomy.
Patient over 75 + 2-3 days of constipation + abdo pain. Dx?
Sigmoid volvulus
Rotation around its mesentery causes “dilation of sigmoid colon” (answer on NBME as what is most likely to be seen in patient).
Sigmoid volvulus Dx?
Abdominal x-ray is used to diagnose, which shows a coffee bean sign, which is one of the highest yield radiographic images on USMLE.
Sigmoid volvulus Tx?
“sigmoidoscopy-guided insertion of rectal tube.
Patient over 70 + chronic constipation + “hard stool palpated in the rectal vault. Dx?
Fecal impaction
Idiopathic, but exacerbated by opioids.
Fecal impaction. Can sometimes cause fecal incontinence and paradoxical overflow diarrhea leading to encopresis (i.e., word for shitting yo pants).
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Fecal impaction Tx?
enema and laxatives
Bleeding per rectum that will be described as “blood on the toilet paper,” or “blood that drips into the toilet bowl.” Dx?
Hemorrhoids
Bleeding from internal hemorrhoids is painless. These are above the pectinate line in the anal canal.
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Bleeding from external hemorrhoids is painful. These are below the pectinate line.
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hemorrhoids risk factors?
Pregnancy and cirrhosis are risk factors.
hemorrhoids Dx? 2
Rectal exam —> ANOSCOPY
hemorrhoids Tx? conservative
Often self-resolve and can be managed conservatively with sitz bath, NSAIDs, and dietary fiber.
hemorrhoids Tx? Surgical
However, if USMLE forces you to choose surgical management for more severe cases, the answer is rubber band ligation.
Young adult who has painful bowel movements +/- blood in the stool. Dx?
Anal fissure
Anal fissure. The key detail is they refuse the rectal exam because the pain is so bad.
For whatever reason, they can also say there’s an associated skin tag. I’ve seen this more than once, where the student says, “What’s with the skin tag?” No fucking idea.
Anal fissure. mechanism?
“increased anal sphincter tone.”
Anal fissure. Tx?
Tx on 2CK Surg is sitz bath.
Anal fissure. Tx if forces to choose drugs?
topical nitrates or diltiazem is used.
Cystic mass at the superior aspect of the gluteal cleft. Contains hair; often caused by ingrown hairs. Dx?
Pilonidal cyst/abscess
Pilonidal cyst/abscess Tx?
Tx on 2CK Surg = incision and drainage
Painful, erythematous mass near anal verge.
Increased risk in Crohn and diabetes. Dx?
incision and drainage.
Anal malignancy. cancer at anal verge + asks for next best step in management?
answer = colonoscopy; excision is wrong answer. Presumably the scoping is done to first investigate the extent of the disease, as that might alter management.
