Gastrointestinal and hepatobiliary system pathology
Gastrointestinal system
Structure and function [Fig. 10-1]
• Function
– absorption of nutrients, excretion of waste
• Structure
– 4 layered tube
• mucosa [epithelium, lamina propria, muscularis mucosae]
• submucosa
• muscularis propria
• serosa [peritoneum]
– blood vessels, lymphatics, nerves (ANS)
– MALT
Oral cavity pathology
• Cleft lip and palate
– congenital anomalies of the lips and palate due to failure of fusion of facial processes
– multifactorial disorders, varying severities
• Dental caries (cavities)
[Fig. 10-2]
– disease of teeth due to bacterial erosion of tooth structure
– Streptococcus mutans thrives in saliva with sugar
– plaque promotes attachment of bacteria
– Complications
• pulpitis
• apical abscess
• periapical granuloma
• radicular cyst
• Periodontitis
– inflammation of periodontal recesses (gingiva, periodontal membrane, alveolar bone)
– most common cause of tooth loss
• Stomatitis
– inflammation of the mouth (oral mucosa)
– infectious causes
• viruses [herpes], bacteria, fungi [candida]
– non infectious causes
• aphthous ulcers
• immunologic
Oral cavity neoplasms
• Leukoplakia is clinical term for a persistent white lesion
• Erythroplakia is clinical term for a persistent red lesion
• Malignant oral neoplasms
– arise from epithelium in the oral cavity
– usually squamous cell carcinomas (>95%)
– risk factors include tobacco, alcohol
– may present as leukoplakia
– most common locations are anterior 2/3 of tongue, lower lip
– metastasize to regional lymph nodes
– treatment with surgery and radiation (5 yr survival = 45%)
