Infectious diseases with tonsillitis. Diphtheria Lecturer GorishnaIvannaLubomyrivna
Plan of the lecture • Definition of Diphtheria • Etiology • Transmission • Pathogenesis • Classification and clinical presentation • Complications • Diagnostic tests • Differential diagnose • Treatment • Prevention
Diphtheria is Diphtheria is an acute toxicoinfection caused by toxigenic strains of Corynebacterium diphtheriae, characterized by a local lesion consisting of a membrane. The constitutional symptoms are due to exotoxin circulation, which has a special affinity for nerve tissue, heart muscle and kidneys.
ETIOLOGY • Corynebacterium species are aerobic, nonencapsulated, non-sporeforming, mostly nonmotile, gram-positive bacilli. • Sensitive to high temperature and disinfection • Stabile to freezing and dryness • Three biotypes – • mitis • gravis • intermedius
Transmission Transmission is from person-to-person (from a patientorcarrier) • through direct contact • or airborne respiratory droplets Thesematerialsincludedischargefromthenose, throat, andlesionsontheskin, eyesandeventhevagina. Contagious index – 10-15% Seasonality – autumn-winter Immunity – instable
Incubation period • Short (from one to seven days)
Pathogenesis • Entrance for the infection: throat, nose, larynx, sex organs, wound. • Dissemination of the Corynebacterium, production of exotoxin. • Local toxin effects with membranous inflammation. • Toxemia. • Diffuse toxic effects on kidneys, suprarenal glands, cardiovascular system, and peripheral nervous system.
Fibrinous inflammation • Diphtheritic (on flat multilayer epithelium) • Crupous (on cylindrical one layer epithelium)
Classification of Diphtheria • Diphtheria of the tonsils and pharynx • localized (catarrhal, islet-like, membranous) • spread form • toxic form: • I degree • II degree • III degree • hypertoxic • hemorrhagic form • gangrenous form
Classification of Diphtheria Diphtheria of the respiratory tract (croup) • Localized croup (laryngitis) • Spread croup • laryngotracheitis • laryngotracheobronchitis • Stages of croup • Catarrhal croup • Stenosis • Compensated • Subcompensated • Decompensated • Asphyxia
Classification of Diphtheria • Diphtheria of the nasopharynx(adenoiditis) • Diphtheria of the nose • localized • catarrhal • islet-like • membranous • Spread • toxic • Combined form • Rare forms (localized, spread, toxic) • eye • ear • skin • genital tract
Classification of Diphtheria The course of disease • With complication • Without complication
Classification of Diphtheria Bacilli carrying • Transitional carrying • Short time – up to 2 wks • Prolong carrying - more than 1 mo • Chronic carrying – more than 6 mo
Complications • early: • Toxic shock syndrome; • DIC syndrome • Acute adrenal insufficiency; • Renal insufficiency • Respiratory insufficiency • Plural organs insufficiency • (in the end of 1st to 2nd week) nephritis; myocarditis; peripheral cranial nerves palsies; • late (on the 3rd to 7th week): myocarditis; peripheral spinal nerves palsies.
Death may occur from • Toxemia toward the end of the firth week • Cardiac failure from toxic myocarditis (second week of illness) • Respiratory failure due to peripheral neuritis affecting the vagus nerve (third to seventh week)
Diagnostic tests • used to confirm infection combine isolation of C diphtheriae on cultures with toxigenicity testing. • Bacteriologic culturing is essential to confirm the diagnosis of diphtheria. • Toxigenicity testing: Perform toxigenicity testing using the Elek test to determine if the C diphtheriae isolate produces toxin. • Polymerase chain reaction
Differential diagnose • Diphtheria of the pharynx must be differentiated from scarlet fever, acute bacterial tonsillitis, infectious mononucleosis; • diphtheria of the upper respiratory tract– with viral croup caused by parainfluenza, measles, chickenpox, and influenza viruses.
Viral croup: • Acute development • Stenosis of1st-2nddegree, • Absence of gradual development, • Absence of aphonia, loud voice • Other clinical signs (rash, rhinitis, pharyngitis) • Moderate or severe intoxication, • Edema of the sub vocal space, • Negative bacterial culture
Treatment • Absolute bed regime (2-3 wks) • Diphtheritic antitoxin therapy • Antibacterial therapy • BENZYLPENICILLIN Na 50-100 000 lU/kg/day • Erythromycin 40-50 мg/кg/day • Roxitromycin 5-8 mg/kg • Rifampicin 10-15 мg/кg/day • Antiseptic fluids locally • Desensitization (suprastinum) • Vitamins B-group, C • Disintoxication therapy (50-100 ml/kg/day) • In case of severe form corticosteroids therapy prednisolone 2-3 mg/kg/day hydrocortizone 5-10 mg/kg/day
In case of toxic shock syndrome: • - Immediately intravenous infusion of DAT with prednisone intravenously 30-50 mg before DAT; • - Prednisone 10-20 mg/kg/day in equal doses 2-4 times per day; • - Detoxication, correction of acid-base stability and electrolytes; • - Dopamine, trental, corglicon.
In case of diphtheria of the larynx(except DAT): • - Inhalation of antiedematous drugs (2% NaHCO3, hydrocortisone, euphyllin, and mucolithics); • suctioning of membranes and mucus; • inhalation of oxygen; • in the III stage of stenosis – intubation; • In case of spread croup, combined with diphtheria of pharynx – tracheotomy.
Carriers’ treatment: • Erythromycin 40-50 мg/кg/day • Roxitromycin 5-8 mg/kg • Rifampicin 10-15 мg/кg/day • Antiseptic fluids locally • Vitamins B-group, C • Immune modulators in case of chronic site of infection, • Tonsillectomy, adenotomy in case of chronic carrying.
Patients discharge • healthy; • Patient should be isolated until three consecutive throat swabs take 24 hrs apart after stopping treatment, are negative • Mild and moderate in 14-21 days; • Severe – in 30-60 days.
Prevention specific • Immunization by DTP vaccine from 3 months age 3 times in 30 days interval (3, 4, 5 months), revaccination in 18 months (DTP), 6, 14, 18 years (DT), later – every 10 years.
Prevention nonspecific • Close contacts who were previously immunized longer then 5 years before should receive booster dose of diphtherial toxicoid • Antibiotic (erythromycin, rifampin) orally for 7 days • Revealing, sanation of healthy infected persons, • contacts’ examination for 10 days, • disinfection of epidemic focus.