Respiratory Diseases

1. Respiratory Diseases Lin Guangyu Department of Pediatrics, The Second Affiliated Hospital to Medical College, Shantou University

3. General Introduction Respiratory disorders important as • They account for 50 % of consultations with general practitioners for acute illness in young children and a third of consultations in older children • Respiratory illness leads to 20-35 % of acute paediatric admissions to hospital, some of which are life-threatening • Asthma is the most common chronic illness of childhood in the world

4. Acute Upper Respiratory Infection (AURI)

5. Introduction • AURIs are the most frequently occurring illness in children. On average, children acquire three to eight AURIs every year. AURIs are generally caused by the viruses. • There are little difference in the incidence of colds by sex, race, or geograhpic region. • Environmental factors that increase the likelihood of acquiring cold include attendance at child care facilities, smoking, passive exposure to smoke, low income, crowding and psychologic stress.

6. Etiology • Viruses • Cold viruses may be transmitted by three routes: • Large-particle droplets, which can travel a short distance to directly inoculate another person • Small-particle aerosols, which can travel longer distances and deposit directly in alveoli of other individuals • Secretion, which are transmitted by direct physical contact

7. Etiology • Common viruses that usually cause common colds • Rhinoviruses • Parainfluenza or influenza viruses • Respiratory Syncytial Virus (RSV) • Coronaviruses • Adenovirus • Enteroviruses • Coxsackie Virus and ECHO Virus • Reoviruses

8. Etiology • The common cold has over 200 known viral causes: • 30% are rhinoviruses. • 40% are unknown. • 15% are influenza or parainfluenza viruses. • 10% are coronaviruses.(20% in adult.) • 5% are enteroviruses.

9. Etiology • Parainfluenza viruses (types 1～4) often produce lower respiratory disease but, particularly in reinfections, the symptoms may present as uncomplicated AURIs. • RSV often begins in infants as a AURI but spreads to the lower respiratory tract.

10. Etiology • Bacteria • A bacteral infection is secondary. • The most common bacteria: • Streptococcus hemolyticus • Influenza Bacillus • Streptococcus Pneumoniae • Mycoplasma Pneumoniae

11. Etiology • Other causes • Characteristic of respiratory anatomy and physiology in children • Characteristic of respiratory immunity in children • Body states:Deficiency of vitamins and trace elements malnutrition • Environmental factors

12. Pathogenesis • The offending virus invades the epithelial cells of URT. • Inflammatory mediators are released. • They alter the vascular permeability and cause tissue edema and stuffiness. • Stimulation of cholinergic nerves in the nose and URT leads to increased mucus production (rhinorrhea) and occasionally to bronchocontriction • Injury to cilia in the nasal epithelial cells may decrease ciliary function and impair clearance of nasal secretions.

13. Clinical Manifestations • Symptoms of Respiratory System • Nasal obstruction • Rhinorrhea • Sneezing • Coughing • Pharyngodynia

14. Clinical Manifestation • General Symptoms • Sudden onset • Anorexia • Fever • Vomiting • Diarrhea • Restlessness, Convulsion • Abdominal pain

15. Clinical Manifestations • Signs • Congestion of throat • Swelling of tonsil • Submaxillary lymphadenopathy and cervical lymphadenopathy • Skin rash

16. Clinical Manifestations • Symptoms of older children with URIs • The patients usually experiences a sudden onset of clear or mucoid rinorrhea, nasal congestion, and fever. • Mild sore throat, cough, sneezing, and eye irritation may develop. • Headache, malaise, myalgia, and decreased appetite usually occur. • The nose, throat, and tympanic membrane can appear red and inflamed. • Most systemic symptoms subside within 5～7 days.

17. Clinical Manifestations • Infants with URIs • Infants have a more general presentation. • High-grade fever • Irritable and restless • Feeding and sleeping difficult • Vomiting and diarrhea

18. Specific Types of URIs • Herpangina • Herpangina is caused by coxsackie A group viruses. • Herpangina is characterized by an acute onset of fever and oropharyngeal vesicles ( 3-4mm in size) and ulcers surrounded by an ery, and sometimes the characteristic lesions are found on the soft palate and uvula. • Dysphagia , vomiting , and anorexia also occur. • Symptoms disappear in 1 week.

19. Specific Types of URIs • Pharyngo-conjunctival fever • This disorder is caused by type 3 or 7 adenovirus. • Pharyngitis, conjunctivitis, fever and cervical lymphadenopathy are the main findings. • Symptoms disappear in 1 ～2 weeks.

20. Complications • Acute otitis media • Paranasal sinusitis • Neck lymphrnoditis • Retropharyngeal abscess • Laryngitis • Lower respiratory tract disease • Acute glomerulonephritis and rheumatic fever

21. Laboratory Test • White cell count • The viral infections is normal to low. • The bacterial infections or viral-bacterial infection is high. • Laboratory diagnosis of viral infections • Antigen or nucleic acid detection • Serologic testing • Isolation of viruses by culture of the throat or nasopharynx • Use of monoclonal antibodies • Polymerase chain reaction (PCR)

22. Diagnosis and Differential Diagnosis • Diagnosis • According to symptoms and signs, AURIs are easily diagnosed. • A key decision in evaluating children with AURIs is to determine whether the illness is just a common cold or whether a secondary infection or complication is present.

23. Diagnosis and Differential Diagnosis • Differential Diagnosis • Influenza • Epidemiologic history • Severe general symptoms • Acute infectious diseases during early period • History • Clinical manifestations • Laboratory findings • Acute appendicitis • Periumbilical abdominal pain, which then localizes to the right lower quadrant • Higher white blood cell counts

24. Treatment • General treatment • Heteropathy • The treatment of AURIs is usually symptomatic • Etiological treatment • Antivirotic:Virazole Persantine • Antibiotics

25. Conclusive Discussion The term URTI embraces a number of different conditions. • Common cold (coryza) • Sore throat (pharyngitis, including tonsillitis) • Acute otitis media • Sinusitis (relatively uncommon)

26. Bye-bye !