Colorectal, in full.

General post-polypectomy surveillance still follows USMSTF 2020 (Gupta et al.), which has not been replaced: 1-2 tubular adenomas <10 mm, 7-10 years; 3-4 tubular adenomas <10 mm, 3-5 years; 5-10 tubular adenomas <10 mm, any adenoma ≥10 mm, or an adenoma with tubulovillous/villous histology or high-grade dysplasia, 3 years; >10 adenomas, 1 year with polyposis evaluation. For serrated polyps: 1-2 SSLs <10 mm, 5-10 years; 3-4 SSLs <10 mm or a hyperplastic polyp ≥10 mm, 3-5 years; an SSL ≥10 mm, an SSL with dysplasia, or a traditional serrated adenoma, 3 years. When findings are mixed, use the shortest interval indicated. Before applying an interval, confirm complete resection and adequate prep. Piecemeal resections get a site check, and malignant (T1) polyps go to a tumor-board pathway. Serrated polyposis syndrome (SPS) is now governed by a separate USMSTF consensus statement (Rex et al., published simultaneously in Gastroenterology, Am J Gastroenterol and GIE on 2026-09-30). It has 11 recommendations. Diagnose SPS with the 2019 WHO criteria, which count the size, cumulative lifetime number and location of serrated polyps. Until SPS is diagnosed, record the number, size and location of serrated polyps in every colonoscopy report. SPS colonoscopy should be done by endoscopists with documented adequate SSL detection, using high-definition white light with or without chromoendoscopy. Without concurrent CRC, endoscopy is preferred over surgery for primary management. If the polyp burden cannot be managed endoscopically, refer to an advanced endoscopic resection expert before surgery. Resect SSLs and hyperplastic polyps by cold snare, with submucosal injection for larger lesions. Do clearance colonoscopy at 3-6 months, then surveil every 1-2 years. Consider 3-year intervals if the burden is greatly reduced at surveillance. First-degree relatives start colonoscopy at age 40, or 10 years before the youngest CRC diagnosis in the family, or 5 years before the youngest SPS diagnosis, whichever comes first. SPS has no established genetic basis, so germline testing is recommended only when concurrent non-serrated polyps suggest a heritable syndrome. Lynch, FAP/AFAP and MAP criteria still trigger genetic evaluation.

U.S. Multi-Society Task Force (2017 guideline, revised by the 2022 focused update on age to start and stop): offer average-risk colorectal cancer screening to everyone aged 45-75. Screening at 45-49 is a weaker recommendation than at 50-75. Colonoscopy every 10 years and annual FIT are the Tier 1 cornerstones. Tier 2 alternatives are multi-target stool DNA every 3 years, CT colonography every 5 years, and flexible sigmoidoscopy every 5-10 years. Capsule colonoscopy every 5 years is Tier 3. Any abnormal non-colonoscopy test requires a diagnostic colonoscopy, and a stool test should not be offered to a patient who would decline follow-up colonoscopy. Patients who are up to date with negative prior screening, particularly a high-quality colonoscopy, may consider stopping at 75 or when life expectancy is under 10 years. Decisions at 76-85 are individualized by health and prior screening, and screening after 85 is not recommended. The American Cancer Society's May 2026 guideline agrees on the 45-75 range, no screening after 85, and colonoscopy as the preferred option. It adds the next-generation mt-sDNA test and the multitarget stool RNA test (ColoSense), both every 3 years, and it adds an FDA-approved blood-based cfDNA test (Shield) only for people who decline or do not complete visual or stool screening. ACS says a positive stool or blood test should be followed by colonoscopy, preferably within 6 months. The 2026 ASGE paper on follow-up after an abnormal stool test is an implementation review (navigation, tracking, direct-access colonoscopy), not a new screening guideline.

In a patient with proctitis symptoms and receptive anal sex history, test with rectal NAAT for gonorrhea and chlamydia (LGV testing if positive), syphilis serology, HSV PCR from ulcers, stool studies for enteric pathogens in proctocolitis, plus HIV and hepatitis testing. Give empiric ceftriaxone 500 mg IM once plus doxycycline 100 mg BID for 7 days presumptively while awaiting results, started whenever the presentation is consistent with acute proctitis (anorectal exudate on exam or polymorphonuclear leukocytes on a Gram-stained anorectal smear, or, if anoscopy/Gram stain is unavailable, in a patient reporting receptive anal exposure) rather than only once symptoms are "moderate-severe", then tailor therapy by pathogen (extend doxycycline to the full 21-day course presumptively for LGV when bloody discharge, perianal or mucosal ulcers, or tenesmus accompany a positive rectal chlamydia NAAT, rather than waiting for confirmed LGV; penicillin G benzathine for syphilis, antivirals for HSV). Include partner notification and treatment, sexual health counseling, and repeat STI testing at 3 months.

U.S. Multi-Society Task Force (2017 guideline, revised by the 2022 focused update on age to start and stop): offer average-risk colorectal cancer screening to everyone aged 45-75. Screening at 45-49 is a weaker recommendation than at 50-75. Colonoscopy every 10 years and annual FIT are the Tier 1 cornerstones. Tier 2 alternatives are multi-target stool DNA every 3 years, CT colonography every 5 years, and flexible sigmoidoscopy every 5-10 years. Capsule colonoscopy every 5 years is Tier 3. Any abnormal non-colonoscopy test requires a diagnostic colonoscopy, and a stool test should not be offered to a patient who would decline follow-up colonoscopy. Patients who are up to date with negative prior screening, particularly a high-quality colonoscopy, may consider stopping at 75 or when life expectancy is under 10 years. Decisions at 76-85 are individualized by health and prior screening, and screening after 85 is not recommended. The American Cancer Society's May 2026 guideline agrees on the 45-75 range, no screening after 85, and colonoscopy as the preferred option. It adds the next-generation mt-sDNA test and the multitarget stool RNA test (ColoSense), both every 3 years, and it adds an FDA-approved blood-based cfDNA test (Shield) only for people who decline or do not complete visual or stool screening. ACS says a positive stool or blood test should be followed by colonoscopy, preferably within 6 months. The 2026 ASGE paper on follow-up after an abnormal stool test is an implementation review (navigation, tracking, direct-access colonoscopy), not a new screening guideline.

Triage suspected perforation with immediate IV access (2 large-bore IVs) and assessment of perfusion in parallel with diagnostics; obtain upright CXR and CT abdomen/pelvis (most sensitive/specific) plus labs and lactate, and start empiric broad-spectrum antibiotics. Fluid therapy is stratified by perfusion status, not given as a fixed protocol for all comers: in adults with sepsis-induced hypoperfusion or septic shock, give at least 30 mL/kg IV crystalloid within the first 3 hours (Surviving Sepsis Campaign 2026; conditional recommendation, low-certainty evidence), selecting the initial volume by individual patient characteristics and context (use adjusted or ideal body weight if BMI >30 kg/m²) with frequent, ongoing reassessment to avoid under- or over-resuscitation, alongside sepsis care: blood cultures as soon as possible and ideally before antimicrobials, lactate with serial measurement to guide resuscitation, and vasopressors if hypotension persists despite fluids. In patients without sepsis-induced hypoperfusion or shock, do not give protocolized volume resuscitation; use maintenance fluids or small individualized boluses guided by hemodynamic reassessment, and in fluid-sensitive patients (e.g., heart failure, end-stage renal disease) use smaller individualized boluses with close reassessment rather than a fixed weight-based volume. Obtain mandatory emergency surgical consultation for any confirmed perforation, hard peritoneal signs, free air, or hemodynamic instability, proceeding to exploratory laparotomy/laparoscopy or cause-specific surgery (Graham patch, Hartmann, colectomy). Selected contained post-procedural perforations that are small, clip-amenable, and hemodynamically stable may be managed conservatively with ICU monitoring, NPO, antibiotics, and serial imaging.