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Lesion of the Upper Respiratory Tract
Izatty Lim0308188
Acute Infections
Nasopharyngeal Carcinoma
Laryngeal Tumors
MBBS Batch 410 December 2013
INTRODUCTION Lesion
o A localized pathological change in a bodily organ or tissue
Upper Respiratory Tract o Composed of the nose and nasal cavity, paranasal sinuses,
pharynx (throat), larynx. o Conducting portion
ACUTE INFECTIONS OF UPPER RESPIRATORY TRACT
among the most common afflictions of humans Manifesting as “common cold” occur in the fall and winter & are self-limiting complicated by the development of bacterial
otitis media or sinusitis (minority)
most common pathogens:o Rhinoviruseso coronaviruses, respiratory syncytial viruses,
parainfluenza and influenza viruses, adenoviruses, enteroviruses, and sometimes even group A β-hemolytic streptococci also have been implicated
o 40% cases, cause cannot be determined
ACUTE INFECTIONS OF UPPER RESPIRATORY TRACT
signs and symptoms localized to the pharynx, epiglottis, or larynx:o Acute pharyngitiso Acute bacterial epiglottiso Acute laryngitis
Clinical features:o nasal congestion + watery dischargeo Sneezingo scratchyo dry sore throato slight increase in temperature ( young children)
ACUTE PHARYNGITISo Manifest as sore throat, may caused by a host of agents. o Mild(most common) minimal physical findings frequently
accompanies a cold o More severe tonsillitis, associated with marked hyperemia +
exudates, ( β-hemolytic streptococcal and adenovirus infections)
Streptococcal tonsillitis o important to recognize & treat early peritonsillar abscesses (“quinsy”) or
poststreptococcal glomerulonephritis & acute rheumatic fever.
Coxsackievirus A infection pharyngeal vesicles and ulcers (herpangina).
Infectious mononucleosiso caused by Epstein-Barr virus (EBV) important cause of pharyngitiso bears the moniker of “kissing disease”—common mode of transmission
ACUTE BACTERIAL EPIGLOTTITIS
o young children o caused by H. influenzao pain & airway obstruction are the major findingso abrupt onset
* need to maintain an open airway for a child ( fatal consequences)
vaccination against H. influenzae .
ACUTE LARYNGITIS
causes:o inhalation of irritants o allergic reactionso agents that produce the common cold
usually involve:o pharynx o nasal passages o larynx.
UNCOMMON BUT IMPORTANT FORMS OF LARYNGITIS
In children, parainfluenza virus most common cause of
laryngotracheobronchitis (croup) o other agents (eg. respiratory syncytial virus) may also precipitate this condition.
self-limitedo croup may cause frightening inspiratory stridor and harsh, persistent cough.
laryngeal inflammatory reactiono narrow the airway sufficiently to cause respiratory failure.
Tuberculous and diphtheritic. o consequence of protracted active tuberculosis infected sputum is coughed up. o uncommon immunization of young children against diphtheria toxin.
Corynebacterium diphtheria inhaled & implants on the mucosa of the upper airways o laborates a powerful exotoxin that causes necrosis of the mucosal epithelium + dense
fibrinopurulent exudate classic superficial, dirty-gray pseudomembrane of diphtheria. o The major hazards: sloughing and aspiration of the pseudomembrane (causing obstruction of
major airways) and absorption of bacterial exotoxins (producing myocarditis, peripheral neuropathy, or other tissue injury).
Predispose the patient to secondary bacterial infection, particularly by staphylococci, streptococci, and H. influenza
NASOPHARYNGEAL CARCINOMA
rare neoplasm invade locally spread to cervical lymph nodes metastasize to distant sites tend to be radiosensitive 5-year survival rates of 50% are reported for even
advanced cancers
Important due too strong epidemiologic links to EBVo the high frequency among Chinese (possibility of genetic susceptibility)
EBV genome found in all nasopharyngeal carcinoma
Links to Epstein-Barr Virus
NASOPHARYNGEAL CARCINOMA
3 histologic variants:o Keratinizing squamous cell carcinomao Non-keratinizing squamous cell carcinoma o Undifferentiated carcinoma (most common & closely linked to
EBV)• large epithelial cells having indistinct cell borders • prominent eosinophilic nucleoli
striking influx of mature lymphocytes o similar in infectious mononucleosis
appearance similar to non-Hodgkin presence of large neoplastic cells with background of reactive lymphocytes
immunohistochemical stains epithelial nature of the malignant cells
LARYNGEAL TUMORS
variety of non-neoplastic, benign & malignant neoplasms of squamous epithelial and mesenchymal
origin may arise in the larynx, but only vocal cord nodules, papillomas, and squamous cell carcinomas are significant
most common presenting feature is hoarseness
Nonmalignant Lesions Vocal cord nodules ("polyps")
o smooth, hemispherical protrusions (<0.5 cm in diameter) o Located (most often) on the true vocal cordso fibrous tissue o covered by stratified squamous mucosa o heavy smokers or singers (singer's nodes) result of
chronic irritation/abuse. o Lead to breathy and hoarse voice
pathogenesiso represent a response to vocal trauma trauma of the laryngeal mucosao alteration of the permeability of blood vessels o allowing the extravasation of edema fluid, fibrin or erythrocyteso reactive processes develop with the formation of labyrinthine vascular
spaces
Nonmalignant Lesions Laryngeal papilloma human papillomavirus (HPV) types 6 & 11
o benign, often spontaneously regress at puberty. o usually on true vocal cordso forms a soft, raspberry-like excrescence (rarely more than 1 cm in
diameter)o Histologically,
• multiple, slender, finger-like projections • supported by central fibrovascular cores • covered by an orderly, typical, stratified squamous epithelium.
o papilloma on the free edge of the vocal cord ulceration + hemoptysis.o usually single in adultso often multiple in children recurrent respiratory papillomatosis (RRP),
tendency to recur after excision believed due to vertical transmission from an infected mother during delivery.
o HPV vaccine protect women in reproductive age group against types 6 and 11 • prevention of RRP in children
Carcinoma of the Larynx
represents only 2% of all cancers. > 40 years men (7 : 1) ~95% are typical squamous cell lesions. adenocarcinomas (rare), presumably arising from
mucous glands. 60% - 75% cases glottic tumors
o usually keratinizing, well- to moderately differentiated
o Non-keratinizing & poorly differentiated carcinomas may also be seen
25% - 40% supraglottic, <5% subglottic
Carcinoma of the Larynx
major etiologic factors include :o smokingo alcoholo previous radiation exposureo Human papillomavirus sequences
begin as in situ lesions pearly gray, wrinkled plaques on the mucosal surface ulcerating and fungating
Clinical manifestation persistent hoarseness
Surgery/ radiation/combined therapeutic treatments many patients can be curedo but ~1/3 die distal respiratory passages / widespread metastases and
cachexia
REFERENCES Robbins Basic Pathology 9th Edition
• By Kumar Abbas Aster
Pathogenesis of vocal cord polypso http://www.ncbi.nlm.nih.gov/pubmed/7114717
THANK YOU