INFECTIONS OF RESPIRATORY TRACTThe peak incidence of respiratory infections in general is during the months of December to February . The attack rate is higher among the children than the adult and especially severe on those under 3 yrs and more than one affected among the family.
The causal agents are a wide variety of viruses and bacteria , usually start with viral infection followed by secondary bacterial invasion .A wide range of clinical pattern from the trivial to the fatal can produce by many viruses , each of which may produce essentially similar clinical illness ,
Classification of acute respiratory diseases is difficult because the isolation of the viruses is slow and requiring laboratory facilities which are not universally available . On anther hand an anatomical classification can not provide a satisfactory basis because a single virus can affect the respiratory mucous membrane which is continuous from the nose to the alveoli . Further more some of the viruses do not confined to respiratory tract alone ,but also may invade the GIT ,mesenteric lymph nodes and CNS .
There are 3 main groups of viruses that affect the respiratory tract . ( 1) . Myxo viruses include the influenza A and B , respiratory syncytial virus and para influenza virus . (2 ) . the adenoviruses contain a large number of different types ,some endemic or others epidemic . ( 3) . the picorna viruses are two types ,entero virus such as coxcacke , ECHO virus and rhinoviruses of many serological types . There is no doubt that RSV is the commonest virus and most severe one ,causing infection of the infant and young children and can cause death in absence of bacterial infection .
UPPER RESPIRATORY TRACT INFECTIONS majority cases including these in which tonsillitis is present are due to the virus and few cases of tonsillitis and pharyngitis are due to bacteria of Beta –hemolytic streptococci .
Clinical features :
Upper respiratory infections vary widely in their clinical features Depend on :---
(1 ) . the area of maximum involvement
( 2 ) . the age of the patient .
( 3) . the causative agent .
Rhinitis with nasal obstruction and mucopurelent discharge may seriously interfere with feeding in the infant whereas a similar common cold in toddler may result only in a mild malaise and low grade fever and nasal discharge .
In most cases however the pharynx shows acute hyperaemia and some edema ,may with cervical adenitis that present with brisk fever ,irritability and anorexia .
W hen the cause adenovirus type 3 ,conjunctivitis and posterior cervical lymphodenitis are often present
The direct inspection of the throat is important because the young child rarely complained of sore throat .When the larynx affected can cause strider
When trachea affected the symptoms ,harsh cough ,sometime with retrosternal pain ,often worsen during night . In other cases the prominent complain are abdominal pain and vomiting due to mesenteric lymph nodes , so the differential diagnosis from appendicitis may be difficult , but the viral infection are associated with high fever and flushed hot skin and often absence of rigidity and muscle tenderness . In few cases headache and neck stiffness may arouse the suspicion of meningitis
IT IS WISER TO PERFORM A LUMBER PUNCTURE THAN TO RISK LEAVING A PYOGENIC MENINGITIS INADEQUATELY TREATED
If the tonsils affected they are grossly hyperemic and swollen with yellow to white
Exudates may appear in crypts with enlarged tender lymph nodes .
TREATMENT OF UPPER RESPIRATORY INFECTIONS1-The room of the patient should be airy with temp. around 18-20 centigrade .
2-good intake of fluid and glucose in form sweetened drinks must be encouraged
3-diet should be light and palatable and the intake of calories is an important in a short illness.
4-tepid sponging is indicated if the rectal temp. rises above 39 c .
5-pain and high temp. can relieved by paracetamol .
6-nasal obstruction may be temporarily relieved by the use in each nostril before each feed of 2 drops of normal saline .
7-throat swab should be always be taken for culture when the pharynx is inflamed and when the hemolytic streptococcus are isolated antibiotic should be given such as benzyl penicillin 5oo,ooo unites I.m. twice daily for 3 days and followed by oral penicillin 250 four times daily for a further four days .
1- CROUPThe most common syndrome of infectious upper obstruction is croup or acute infectious laryngo tracheobronchitis .
Croup is of viral etiology para-influenza type 1 ,2 viruses are the most common .
CLINICAL FEATYRES :-
The typical attack begin in a child between 6 mon .-3 yrs.Having symptoms of upper respiratory infections (common cold ) and lasts less than five days .
A brassy cough ,inspiratory strider and respiratory distress may develop slowly or acutely . signs of upper air way obstruction such as labored breathing and marked supra sternal ,inter costal and sub costal retractions are evident on examination .
Associated lower air way diseases accompanied by wheeze and productive cough may present ,although the majority of such children are not seriously ill.
The air way may becomes more severe .
The subglotic space is the major site of obstructive which is caused by edema resulting from the viral inflammation .
Indication of admission to hospital :-
1 . suspected epiglottitis .
2 . progressive strider .
3 . severe distress at rest .
4 . hypoxeamia .
5 . restlessness with pallor or cyanosis .
6 . decrease sensorium .
7 . high fever .
8 . respiratory distress .
Treatment of croup1- keep the child quite as possible and the best calm method for a child with croup is to sit in mother lap .
2- racemic epinephrine inhaler may reduce the edema temporarily producing marked clinical improvement ,but the edema and obstruction soon return and the disease run its course over several days . In severe case epinephrine may be repeated every 20 min .
3 . cool mist adminsterd by tent or face mask may help to prevent drying of the
Secretion around larynx
4 . sedation should be avoided .
5 . systemic administered corticosteroid is beneficial in treating croup ,but Generally is reserved for ill patient .
If the patient is very young ( less than 4 months ) or if symptoms continued
for more than one week ,the patient should undergo care full laryngoscopy, because there is increased possibility that another lesion may present such as
subglottic or hemangioma .
sudden worsening ( fever ,respiratory distress , increased ) this suggests
complicating bacterial tracheitis
6 . Intravenous fluid may be needed in severely distressed child .
2- EPIGLOTTITISAnother syndrome o upper air way obstruction typically occur in older children ( 2-7) yrs and the causative agent H . INFLUENZA type b .
CLINICAL FEAT URES
Epiglottitis is characterized by sudden onset with high fever ,respiratory distress ,fulminant progression ,severe dysphagia and muffled voice .
The patient prefer erect position to breath easily with drooling due to dysphagia .
Epiglottitis is true pediatric emergency because the inflamed airway suddenly May become totally obstructed leading to death ,
Examination of the pharynx should be avoided
DIFFERNTIAL DIAGNOSIS OF EPIGLOTTITIS
1 . severe croup .
2 . becterial tracheitis .
3 . foreign body aspiration .
4 . Retropharyngeal and peritonsillar abscess .
DIAGNOSIS :1 . High suspicion from clinical picture
2. Confirmation depend on direct observation of the inflamed and swollen supraglottic structures and redness of enlarged epiglottis of course examination done at operation room to place nasotracheal or perform tracheostomy .
3 . Isolation of H. influenza from the surface of epiglottis or from Blood culture .
4 . X-ray of lateral neck give us thumb sign of swollen epiglottis .
X-ray in croup give us steeple sign due to narrowed subglottic space. .
TREATMENT :-1 .Admission to the respiratory care unit .
2 . nasotracheal intubations with closed observation to prevent Extubation.
3 .tracheostomy .
5 .antibiotics like ceftriaxone 50 – 75 mg /kg x 2 suitable for H influenza should be given and continued for 7-10 days . Or ampicillin +sulbactam combination should be given Parentrally if H influenza sensitive .
6 . Intravenous fluid may be needed during hospitalization .
7 . the epiglottitis resolve after a few days of antibiotics and the
Patient can be weaned from the tracheostomy
INHERITED LUNG DISEASESCYSTIC FIBROSIS :-
The most common lethal inherited disease of whitish that defined as a disease of the exocrine gland that cause viscoid secretion ,the GIT , and pulmonary system are most commonly and most severely affected .
Cystic fibrosis is inherited as autosomal recessive gene that located on chromosome no. 7 .The defect in cystic fibrosis is thought to be blocked or closed chloride channel in the cell membrane of epithelial cells . this blockage traps chloride ions inside the cell and draws ions and water into the cell . this process results in dehydration of the mucous secretion .
Clinical features :-
1 . respiratory insufficiency , occurs eventually in more than 95 % of all patients and caused by abnormal mucous gland secretion in the airway producing airway obstruction and secondary infection , cough , dyspnea , bronchiectasis , pneumothorax and finely corpulmonale is a late complication .
2.GIT , chronic diarrhea and malabsorption .
3- reproductive defect including sterile male and reduce fertility in females .
4.hepatic manifestation , that ends with portal hypertension .
5.pancreatic with diabetic mellitus .
6.skeletal abnormalities with arthritis and joint pain .
7.nasal including chronic sinusitis with nasal polyps .
Diagnostic criteria of cystic fibrosis :-
1 . positive sweat test by skin test > 6 MEq /L .
2 . typical pulmonary manifestation .
3 . typical GIT manifestation ( meconium ileus , chronic diarrhea , rectal prolapse ,
billiary cirrhosis ) .
4 . positive family history .
1 . treatment of pulmonary problems .
2 . chest physiotherapy ( postural drainage , active cycle of breathing ) .
3 . antibiotics given orally , I.v or aerosol especially for staph. And pseudomonas
infection ( aminoglycosides , cephalosporin can be used ) .
4 . bronchodilators and steroid .
5 . pancreatic enzymes replacement .
6 . vitamins supplement , high calorie and protein diet .
7 . treatment of complication accordingly .
8 . lung transplant .
DISEASES OF PLEURAPLEURAL EFFUSION :--
Accumulation of fluid in the pleural space whenever the local hydrostatic forces pushing fluid out of the vascular space exceed osmotic forces pulling fluid back into the vascular space .
Etiology :-1 . congestive heart failure .
2 . hypoprotienemia .
3 . obstruction of lymphatic drainage .
4 . malignancy .
5 . collagen vascular disease .
6 . infection of pleura is due to strepto cocus , pneumonaie , H . influenza or T .B .
Clinical features :-In general clinical features of primary disease is the presenting symptoms , but the patient may complain from pain , dyspnea , and sings of respiratory insufficiency resulting from compression of the underling lung tissues .
Physical finding include :-
Dullness to percussion , decrease breath sounds , mediastinal shift and decrease tactile fremitus .
Diagnosis :-Is confirmed by chest x-ray . postero- anterior shows uniform opacity with acurved upper border , when air is also present the fluid line is horizontal . decubitus views may be helpful to distinguish fluid collection from other densities
in the thorax . diagnostic thoracocetesis may be necessary to establish the cause of the effusion and to exclude infection .
Most patients with effusion should undergo diagnostic thoracocentesis unless the:- 1 . underling causes for the effusion are clearly evident .
2 . the patient does not have significant respiratory distress .
3 . infection not suspected .
Comparison between transudates and exudates pleural effusion :
1 . low specific gravity < 1.015 high specific gravity
2 . low protein ( < 2.5 g/ dl high protein > 3g / dl
3 . decrease lactic dehydrogenase increase lactic deh.
4 . low cell count high cell count
5 . high PH low PH
6 . normal glucose low glucose
Treatment : -Treatment directed to the underlying condition that cause the effusion and at relief of mechanical consequences of the fluid collection .
Small effusion especially if they are trnsudate usually require no treatment
Large effusion may require drainage with chest tube especially if the fluid is
purulent ( empyema ) .
If the underlying condition is treated successfully the prognosis for patient with pleural effusion including empyema is excellent .
PNEUMOTHORAX:-Is the accumulation of air in the pleural space that may result from external trauma or from leakage of air from the lung or air way ,it may occur spontaneously Predisposing condition include :-
1 . mechanical ventilation .
2 . asthma .
3 . disorder of collagen .
4 . cystic fibrosis .
5 . infection especially staph. Pneumonia , T.B.
6 . Iatrogenic ( tracheostomy , thorachocentesis ) .
Symptoms of pneumothorax :-
Chest pain , dyspnea , and cyanosis . If the air leak accumulate with mediastinum , subcutaneous emphysema may become apparent .
Physical finding :-
Decreased breath sounds , tympanic percussion note , sings of mediastinal shift and subcutaneous crepitance . Few or no physical sings of pneumothorax may be present if the amount of air collection is small , but symptoms may progress rapidly if the air in the pleural space is under pressure ( tension pneumothorax ) with death resulting if the tension not relieved
DIAGNOSIS :-The radiography usually confirms the diagnosis ,although in the infant there may be difficulty in distinguishing pneumothorax from a large diaphragmatic hernia or giant emphysematous bulla , drink of gastrografin usually resolve the difficulty .
TREATMENT OF PNEUMOTHORAX :-The treatment depend on the amount of air collected and the nature of the underling cause ,
Small pneumothorax often do not need treatment and resolve spontaneously .
Large pneumothrax and tension peumothorax require immediate drainage of air .
In emergency situation a simple needle aspiration may sufficient , but placement of chest tube may be require for resolution .
Sclerosing the pleural surfaces to obliterate the pleural space may benefit patient with recurrent pneumothoraces .