GIT-9Miscellaneous
Dr.CSBR.Prasad, M.D.,
Hemorrhoids
• Variceal dilations of the anal and perianal venous plexuses form collaterals that connect the portal and caval venous systems
• Affect about 5% of the general population Causes:– PHT– Constipation (straining at stool)– Venous stasis of pregnancy
Types
• External hemorrhoids: Dilatation of collateral vessels within the inferior hemorrhoidal plexus [located below the anorectal line]
• Internal hemorrhoids: those that result from dilation of the superior hemorrhoidal plexus within the distal rectum
Hemorrhoids
Histology
• Thin-walled, dilated, submucosal vessels that protrude beneath the anal or rectal mucosa
• They are subject to trauma:– Inflammation– Thrombosis– Superficial ulceration
Thin-walled, dilated, submucosal vessels
Thin-walled, dilated, submucosal vessels
Clinical Features
• Pain• Rectal bleeding– Hematochezia
Tumors of the Anal CanalThree types of epithelia lines the anal canal– Upper ⅓ - Columnar type of epithelium– Middle ⅓ - Transitional epithelium / Cloacogenic– Distal ⅓ - Stratified squamous epithelium
Carcinomas:– Adenocarcinoma– Cloacogenic – Transitional cell carcinoma / Basaloid– Squamous cell carcinoma
• HPV associated• Precursor lesion: Condyloma accuminatum
– Mixed carcinomas
Ca. Anal canal
Squamous cell carcinomaSquamous cell carcinoma
AdenocarcinomaAdenocarcinoma
Basaloid (Cloacogenic) CarcinomaBasaloid (Cloacogenic) Carcinoma
Cloacogenic tumor H&E 200x
Basaloid (Cloacogenic) CarcinomaBasaloid (Cloacogenic) Carcinoma
Positive staining with HMWCK in tumor cells (HMWCK antibody), ×200
Paget’s disease of the perianal skinPaget’s disease of the perianal skin
Buschke–Löwenstein tumour
Acute AppendicitisAcute Appendicitis
• Most common in adolescents & young adults• Males• DDs:• Mesenteric lymphadenitis• Acute salpingitis• Ectopic pregnancy• Mittelschmerz • Meckel diverticulitis
Pathogenesis:•Progressive increases in intraluminal pressure that compromise venous outflow– Fecalith– Gall stones– tumor – Mass of worms
•Ischemic injury and stasis of luminal contents:– Favor bacterial proliferation– Trigger inflammatory responses
Fecalith
Morphology• Congested serosal blood vessels• Normal glistening serosal surface turns into a dull, granular
and erythematous• Hall mark of Acute appendicitis:
• Diagnosis of acute appendicitis requires neutrophilic infiltration of the muscularis propria
• Other features:• Mucosal ulceration• Luminal exudation• Fibrinopurulent exudate on the serosa
• Acute suppurative appendicitis• Acute gangrenous appendicitis
Hall mark of Acute appendicitis:Diagnosis of acute appendicitis requires neutrophilic
infiltration of the muscularis propria
Clinical Features• Pain:– Early acute appendicitis: Periumbilical – Later: Localizes to the right lower quadrant
• Classic physical finding is McBurney's sign• Complications of appendicitis:– Perforation– Pyelophlebitis– Portal venous thrombosis– Liver abscess and – Bacteremia
Tumors of the AppendixCarcinoidCarcinoid
• The most common tumor of the appendix is the carcinoid
• Usually discovered incidentally • Usually involves the distal tip of the appendix• 2 to 3 cm in diameter• Nodal metastases are infrequent, and distant
spread is rare
Carcinoiod of appendix
Carcinoid of appendix
Carcinoid of appendix
Carcinoid of appendix
Tumors of the AppendixOthersOthers
• Mucocele• Mucinous cystadenoma – Pseudomyxoma peritoneii
• Mucinous cystadenocarcinoma
Mucocele from mucinous cystadenoma of the appendix
Pseudomyxoma peritonei
Peritoneal disease
Inflammatory DiseasePeritonitis may result from bacterial invasion or chemical irritation and is most often due to: •Leakage of bile or pancreatic enzymes, which produces sterile peritonitis – Perforation or rupture of the biliary system– Acute hemorrhagic pancreatitis
•Foreign material•Endometriosis•Ruptured dermoid cysts •Perforation of abdominal viscera
TumorsTumorsPrimary tumors: •Mesotheliomas – Asbestos exposure
•Desmoplastic small round cell tumor (DSCRT)– t(11;22)(p13;q12)
Secondary tumors: quite common•Ovarian adenocarcinoma•Pancreatic adenocarcinoma•Gastric carcinoma •Appendiceal mucinous carcinomas •Wide variety of tumors of extra-abdominal origin
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