Pneumonia

Dr Rajesh KumarMD (PGI), DM (Neonatology) PGI,

Chandigarh, IndiaRani Children Hospital, Ranchi

Aetiology and epidemiology

• Streptococcus pneumoniae is the most common • Age is a good predictor of the likely pathogens: • Viruses are most commonly found as a cause in younger

children. • In older children, when a bacterial cause is found, it is

most commonly S pneumoniae followed by mycoplasma and chlamydial pneumonia.

• A significant proportion of cases of CAP (8-40%) represent a mixed infection.

• Viruses alone appear to account for 14-35% of CAP in childhood.

• In 20-60% of cases a pathogen is not identified

Aetiology

• Streptococcus pneumoniae – 4% Drummond 2000– 8% Clements 2000– 21% Korppi 1993

• Mycoplasma pneumoniae – 1.5 % Korppi 1993 – 7% Juven 2000 – 33% Eposito 2003

• 20-60% cases a pathogen is not identified• 8-40% represent a mixed infection

Clinical features

• < 3 years: Bacterial pneumonia should be considered in children aged up to 3 years when there is fever of >38.5°C together with chest recession and a respiratory rate of >50/min

• Older children a history of difficulty in breathing is more helpful than clinical signs.

• If wheeze is present in a preschool child, primary bacterial pneumonia is unlikely

• Bacterial LRTI • Viral LRTI

Radiological investigations

• Chest radiography should not be performed routinely in children with mild uncomplicated acute lower respiratory tract infection.

• Radiographic findings are poor indicators of aetiology.

• Follow up chest radiography should only be performed after lobar collapse or for continuing symptoms

General investigations

• Pulse oximetry should be performed in every child admitted to hospital with pneumonia.

• Acute phase reactants do not distinguish between bacterial and viral infections in children and should not be measured routinely

Microbiological investigations

• Blood cultures should be performed in all children suspected of having bacterial pneumonia.

• Nasopharyngeal aspirates from all children under the age of 18 months should be sent for viral antigen detection (such as immunofluoresence) with or without viral culture.

• When significant pleural fluid is present, it should be aspirated for diagnostic purposes, sent for microscopic examination and culture, and a specimen saved for bacterial antigen detection

Indicators for admission to hospital in infants

• oxygen saturation <=92%, cyanosis;

• respiratory rate >70 beats/min;

• difficulty in breathing;

• intermittent apnoea, grunting;

• not feeding;

• family not able to provide appropriate observation or supervision

Indicators for admission to hospital in older children:

• oxygen saturation <=92%, cyanosis;

• respiratory rate >50 breaths/min;

• difficulty in breathing;

• grunting;

• signs of dehydration;

• family not able to provide appropriate observation or supervision.

Streptococcus pneumoniae

• Most common cause of both pneumonia overall and fatal pneumonia.

• Antibiotic resistance has developed worldwide and is most frequent in pneumococcal serotypes that are most prevalent in children (types/groups 6, 14, 19, and 23).

• The incidence of pneumococcal disease is the highest in children < 2 years of age and in adults > 65 years of age.

• Penicillin (penicillin G/amoxicillin) remains the drug of choice for strains that are fully sensitive

• Cefotaxime and ceftriaxone are the first-line alternatives in cases with higher levels of resistance.

Streptococcus pneumoniae: Symptoms and Signs

• Classic description– sudden onset of chills and pleuritic chest pain – followed by fever and then cough productive of rusty

sputum.

• Varies greatly. – Respiratory tract symptoms may be absent, especially

among patients with bacteremic disease.– Lack of fever is not uncommon and indicates a poor

prognosis. – Gastrointestinal symptoms such as nausea, vomiting,

or diarrhea are present in 15 to 20%

Streptococcus pneumoniae

• Bacteremic: 20 to 25% of cases – more frequently have chills and

gastrointestinal symptoms but less often myalgia and respiratory symptoms

• Non Bacteremic:

Streptococcus pneumoniae: CXR

• pulmonary infiltrates are alveolar in nature, most often involving one or more segments within a single lobe.

• Lobar consolidation or an air bronchogram is present only in a minority of cases but is more frequent in patients with bacteremia.

• Pleural effusion is a common finding, whereas a complicating empyema is seen rarely.

Streptococcus pneumoniae: Complications

• 1586 cases,12% had a suppurative complication. Empyema was most common at 7% followed by pulmonary abscess (2.7%), endocarditis (1%), and meningitis (1.2%).

• recent study of 158 patients suppurative complication rate was 3.8%; 1.9% of the patients had empyema, 0.6% had endocarditis, and none had meningitis.

staphylococcal pneumonia

• Clinical presentation is changing

• Most of these staphylococcal strains are methicillin-resistant and are not health care associated.

Atypical Pneumonia

• Most commonly caused by Mycoplasma pneumoniae and Chlamydia pneumoniae

• Incidence varies from 1.5% to 33%

• Clinical presentation - 203 children, – 33% had evidence of M pneumoniae infection– 40% acute onset symptoms, 60% gradual– 19% had lobar changes

Atypical Pneumonia

Age• < 5 years of age

S pneumoniae incidence 8.6/1000 per year M pneumoniae 1.7/1000/year

• 5-15 years S Pneumonia fell to 5.4/1000 M pneumoniae rose to 6.6/1000

Mycoplasma Pneumonia

General management

• The child cared for at home should be reviewed by a general practitioner if deteriorating, or if not improving after 48 hours on treatment.

• Patients whose oxygen saturation is 92% or less while breathing air should be treated with oxygen given by nasal cannulae, head box, or face mask to maintain oxygen saturation above 92% .

• Nasogastric tubes may compromise breathing and should therefore be avoided in severely ill

• children and especially in infants with small nasal passages. If used, the smallest tube should

• be passed down the smallest nostril.. • Intravenous fluids, if needed, should be given at 80%

basal levels and serum electrolytes monitored.

General management

• Chest physiotherapy is not beneficial and should not be performed in children with pneumonia.

• Antipyretics and analgesics can be used to keep the child comfortable and to help coughing.

• In the ill child, minimal handling may reduce metabolic and oxygen requirements.

• Patients on oxygen therapy should have at least 4 hourly observations including oxygen saturation.

INDICATIONS FOR TRANSFER TO INTENSIVE CARE

• Patient is failing to maintain an SaO2 of >92% in FiO of >0.6

• Shock• Recurrent apnoea or slow irregular breathing• Rising respiratory rate and rising pulse rate with

clinical evidence of severe respiratory distress and exhaustion, with or without a raised arterial carbon dioxide tension

Antibiotics

• whether to treat with antibiotics;

• which antibiotic and by which route;

• when to change to oral treatment;

• duration of treatment.

ORAL ANTIBIOTICS

• Amoxicillin: first choice in < 5 years • Alternatives: co-amoxiclav, azithromycin,

cefaclor, erythromycin, clarithromycin • > 5 years.

– Macrolide antibiotics should be used if either mycoplasma or chlamydia pneumonia is suspected

– Amoxicillin should be used as first line treatment at any age if S pneumoniae is thought to be the likely pathogen.

IV antibiotics

• Indications of Intravenous antibiotics– Unable to take oral antibiotics (for example,

because of vomiting)– presents with severe signs and symptoms.

• Antibiotics:– co-amoxiclav, cefuroxime, and cefotaxime.

when to change to oral treatment

• In a patient who is receiving intravenous antibiotic therapy for the treatment of CAP, oral treatment should be considered if there is clear evidence of improvement

Complications and failure to improve

• If a child remains pyrexial or unwell 48 hours after admission, re-evaluation is necessary.

• Answers to the following questions should be sought: – Is the patient having appropriate drug treatment at an

adequate dosage? – Is there a lung complication of pneumonia such as a

collection of pleural fluid with the development of an empyema or evidence of a lung abscess?

• Is the patient not responding because of a complication in the host such as immunosuppression

effusion

• Parapneumonic effusions develop in approximately 40% of bacterial pneumonias admitted to hospital.

• A persisting pyrexia despite adequate antibiotic treatment should always lead the clinician to be suspicious of the development of an empyema.

• Where an effusion is present and the patient is persistently pyrexial, the pleural space should be drained.

COMPLICATIONS OF SPECIFIC INFECTIONS

• S aureus pneumonia: Pneumatoceles occasionally leading to pneumothorax are commonly seen with S aureus pneumonia. The long term outlook is good with normal lung function

• Mycoplasma pneumonia: Complications in almost every body system have been reported in association with M pneumoniae. Rashes are common; the Stevens-Johnson syndrome occurs rarely; haemolytic anaemia, polyarthritis, pancreatitis, hepatitis, pericarditis, myocarditis and neurological complications including encephalitis, aseptic meningitis, transverse myelitis and acute psychosis have all been reported

• Amoxycillin: 8 mg/kg/dose TDS for 7-10 days, may be doubled in severe infection

• Co-amoxyclav: 8 mg/kg/dose TDS for 7-10 days, may be doubled in severe infection

• Azithromycin: 10 mg/kg per day for 5 days• Claritromycin: 7.5 mg/kg BD for 7-10 days• Erythromycin: 10 mg /kg QID for 7-10

days, may be doubled in severe infection

• CEFUROXIME: 30 mg/kg TDS,

• CO AMOXYCLAV: 30 mg/kg TDS

• CEFOTAXIME: 50 mg/kg BD, may be given 6 hourly in severe infections

• AMPICILLIN: 25-100 mg/kg 6 hourly

Physiotherapy

• Physiotherapy did not have any effect on the length of hospital stay, pyrexia, or chest radiographic findings in patients with pneumonia.

• There is no evidence to support the use of physiotherapy including postural drainage, percussion of the chest, or deep breathing exercises. There is a suggestion that physiotherapy is counterproductive, with patients who receive chest physiotherapy being at risk of having a longer duration of fever than the control group.

Systematic Glucocorticoides in wheezing in Children

• Current data do not support the clinical efficacy of glucocorticoids in expiratory wheezing in hospitalized children age <2 years.

• In outpatients <2 years of age systemic glucocorticoid treatment may induce clinical and hospitalization benefit.

• In contrast patients older than 3 years of age with acute asthma clearly benefit from systemic glucocorticoids.

• It is not known whether the differences in the efficacy are related to the differences in viral etiology (RSV vs. rhinovirus), airway diameter, mucus clearance, immunologic maturity or age of the patient

Pediatr Infect Dis J 21(9):873-878, 2002

• Systemic glucocorticoid treatment in these efficacy studies was safe, and clinically meaningful side effects were not reported

• Admitted • Critically ill

• < 3 years:• The First Wheezing Episode. Six studies focused on the first wheezing

episode. Schuh et al.[found that oral dexamethasone given at the emergency department decreased the rate of hospitalization by 57% Goebel et al.[found that children receiving prednisolone had a better clinical score on the second day. The majority of patients were managed as outpatients. On the other hand four studies did not find prednisone or dexamethasone effective in hospitalized children.

• At Least One Previous Wheezing Episode. Fox et al included patients who had suffered at least one previous wheezing episode but did not find prednisolone effective in hospitalized children

• Infants Younger Than 12 Months. Two studies concentrated on the efficacy of systemic steroids for expiratory wheezing in children younger than 1 year). In a study of 46 children Tal et al.[23] found that a combination of dexamethasone and salbutamol improved the clinical score of the children, but the duration of hospital treatment remained the same. On the other hand Roosevelt et al.[11] did not find dexamethasone to be better than placebo in a larger study of 118 children.

• Other Studies in Children Younger Than 3 Years. Eight other studies were of age ranges up to 3 years (Table 1). All children were treated in a hospital. Statistically significant differences in favor of systemic glucocorticoids were found in one-third of the studies. Csonka et al. (submitted for publication) reported that prednisolone reduced the number of long hospitalizations (three nights or more). Van Woensel et al.[18] studied the efficacy of prednisolone in RSV bronchiolitis. Children receiving prednisolone who did not need mechanical ventilation had a better clinical score during the first 3 days, but the duration of hospital stay remained the same. In children receiving mechanical ventilation the duration of hospital stay was shorter in the prednisolone group, but the duration of ventilation therapy was similar in both groups. Daugbjerg et al.[21] found that the clinical score of children receiving prednisolone improved sooner and that the children left the hospital earlier.