BLOCK 12 Viruses of the ENT

Transcription

1 BLOCK 12 Viruses of the ENT

2 Acute infections Introduction Pharyngitis, Common cold, Sinusitis, Otitis media Recurrent infections Herpes zoster oticus Chronic infections HIV and ENT manifestations Neoplasms Benign Malignant : Nasopharyngeal carcinoma, Kaposi sarcoma Sensorineural hearing loss

3 Acute infections of the ENT

4 Viral pharyngitis/tonsillitis/laryngitis Rhinovirus Coronaviruses Adenovirus types Respiratory viruses Parainfluenza virus Influenza virus Coxsackie A and other enteroviruses Herpes Simplex virus (HSV) Epstein-Barr virus (EBV) Cytomegalovirus (CMV) HIV 70% of acute sore throats are caused by viruses

5 Pharyngitis: Causes

6 Enteroviruses: Herpangina Causative agent: Coxsackie A viruses 3 to 10 years of age Present with Flu-like symptoms Painful vesicles and ulcerations of the posterior pharynx and tonsils Vesicles rupture, leaving grayish-white-based ulcers with erythematous borders Self-limiting: resolves in 3 to 7 days Treatment: symptomatic e.g. analgesics

7 Enteroviruses: Hand, Foot and Mouth Disease Cause: Coxsackie A 16 & Enterovirus 71 Most often affects children < 5 years old Presents with Fever Lesions are tender, papules or vesicles on the dorsum of the hands, feet and buttocks Self-limited, resolving within 2 to 3 days Treatment consists of analgesics

8 HSV: Acute herpetic gingivostomatitis Adults have more severe symptoms, with fever, cervical lymphadenopathy and general malaise Vesicles may be limited to the posterior pharynx and tonsils

9 Infectious mononucleosis-like syndromes EBV (70%) CMV HHV-6 Adenovirus HIV acute seroconversion Toxoplasmosis Fever Sore throat Classic Triad Lymphadenopathy

10 EBV=Infectious mononucleosis Most cases: years of age Prodrome: Chills, sweats, feverishness and malaise Sore throat Classic Triad Fever Lymphadenopathy May also have Enlarged tonsils Erythematous pharynx, often covered with a thick continuous exudate Palatal petechiae

11 Acute retroviral syndrome Primary infection with HIV can manifest as a syndrome of fever, nonexudative pharyngitis, arthralgia, myalgia, and lymphadenopathy

12 Common cold Virus % of colds Rhinovirus 30-50% Coronavirus 10-15% Influenza 5-15% RSV 5% Parainfluenza 5% Adenovirus < 5% Picornaviridae family, >100 serotypes of Rhino virus Most commonly : HCoV-229E and HCoV-OC43 Spread by direct contact e.g. hands and droplets Incubation: 24-72h Symptoms: sneezing, nasal congestion and rhinorrhoea, pharyngitis, cough, low grade fever, headache and malaise Complications: otitis media, sinusitis, lower respiratory tract infection Treatment: supportive

13 Acute rhinosinusitis (ARS) Inflammation of the nasal cavity and paranasal sinuses lasting < 4 weeks Subdivided into acute viral rhinosinusitis (AVRS) and acute bacterial rhinosinusitis (ABRS) Causitive agents Viruses: Rhinovirus, influenza etc. Secondary bacterial infection

14 Acute Otitis Media (AOM) Viral URTI is the most common predisposing factor for the development of AOM Predisposes to obstruction of the eustachian tube leading to negative pressure and accumulation of middle ear secretions Impairment in host defences such as normal mucociliary action of the respiratory mucosa

15 Acute Otitis Media (AOM) Bacterial causes Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis Viral causes: Respiratory viruses Respiratory syncytial virus Rhinoviruses Influenza viruses Adenoviruses

16 Recurrent viral infections of the ENT

17 Recurrent infections of the ENT Ramsay Hunt syndrome Herpes zoster oticus VZV establishes a latent infection in sensory ganglia after primary varicella infection During reactivation the virus travels down the axon and re-infects the dermatome supplied by the sensory ganglia to produce painful vesicles on the skin

18 Ramsay Hunt syndrome : Herpes zoster oticus Reactivation of VZV within the geniculate ganglion with subsequent involvement of the eighth cranial nerve Triad of ipsilateral facial paralysis, ear pain, and vesicles in the auditory canal and auricle

19 Chronic infections: HIV and the ENT

20 HIV oral lesions Oral lesions are among the first signs of HIV infection Typical lesions Candidiasis Oral hairy leukoplakia: EBV Herpes labialis: HSV Zoster: VZV Neoplasms Kaposi s sarcoma (HHV-8) Non-Hodgkin lymphoma HIV Oral lesions Periodontal disease Lesions of uncertain origin Recurrent aphthous stomatitis Salivary gland disease Xerostomia: caries

21 HIV: Pharynx, Larynx and Esophagus Candida severe odynophagia when the larynx is affected, hoarseness is a prominent feature HSV CMV

22 Viruses: Neoplasms of the ENT

23 Benign Neoplasms HPV: Laryngeal papillomatosis Benign papillary tumour derived from squamous epithelial cells, generally observed in children HPV6 &11 are involved in the majority Symptoms change of voice and inspiratory stridor; aphonia and respiratory distress in advanced disease

24 Malignant Neoplasms: EBV Epithelial tumours Nasopharyngeal carcinoma High incidence: Southern Chinese population All cases associated with EBV Lymphoepithelial carcinoma (salivary gland) Asian and Greenland Eskimo s All cases associated with EBV Sinonasal undifferentiated carcinoma Strong EBV association in Asians (65%) Lymphoma Nasal/nasopharyngeal T-cell lymphoma Strong EBV association= 90%

25 Malignant Neoplasms HHV-8: Kaposi sarcoma Multifocal vascular tumour caused by HHV-8 AIDS-defining lesion Usually on the soft palate and gingiva

26 Malignant Neoplasms HPV: SCCHN HPV type 16 and 18 is a newly identified causal factor for squamous cell carcinoma of the head and neck (SCCHN) About 25% of all SCCHN contain HPV DNA The association between HPV and SCCHN is strongest for cancers of the tonsil intermediate for the rest of the oropharynx weakest for the oral cavity and larynx

27 Infections associated with sensorineural hearing loss

28 Infections associated with Sensorineural hearing loss Congenital CMV Rubella Childhood Mumps Other Lassa