Prolonged Cough and Fever
Radiology Cases in Pediatric Emergency Medicine
Volume 7, Case 3
Rachel O. Newton-Weaver, MD
Kapiolani Medical Center For Women And Children
University of Hawaii John A. Burns School of Medicine
     This is a 5 year old, male who initially developed 
fever (Tmax 40 degrees C) ten days ago along with 
coughing, a sore throat and mild back pain.  He was 
seen at his health center seven days ago and a throat 
culture was done at that time (eventually negative).  
Over the next five days he continued to have fever and 
cough.  His mother noted him to have decreased 
appetite, increased fatigue and shallow breathing.  He 
did not have any ill contacts, trauma, aspiration/choking 
episodes or foreign travel.   His past medical history is 
negative.  He has not had his 5 year old immunizations, 
but he was up to date prior to this.
     He presented to his primary care physician earlier 
today at which time his vital signs were recorded as:  T 
37.5, P 120, RR 48, BP 100/56 and oxygen saturation 
95-98% in room air.  Although he does not appear to be 
toxic or in obvious distress, he is making soft grunting 
noises and has shallow respirations with diminished 
breath sounds bilaterally. 

     A chest radiograph is ordered.

View chest radiograph.

     Other lab studies done as an outpatient:  CBC WBC 
23,000, 73% segs, 10% bands, 11% lymphocytes and 
6% monocytes, Hgb 10.6, Hct 31.2.  ESR 56.  His 
chemistry panel is normal.
     The chest radiograph demonstrates a large well 
circumscribed consolidated lesion of the right middle 
lobe with an air fluid level.
     Arrangements for hospitalization at a children's 
hospital are made.  Upon admission, he develops 
shaking chills with a temperature of 41 degrees C.  VS 
P 104, RR 52, BP 123/63 and oxygen saturation 96% in 
room air.  He is alert, cooperative and active with some 
tachypnea and shallow respirations noted.  He does not 
appear to be toxic.  Oral mucosa moist, without lesions 
and no dental caries.  Neck is supple without 
lymphadenopathy.  Heart regular without murmur.  
Lung exam is significant for mild tachypnea, shallow 
respirations, decreased breath sounds at both bases 
(right > left).  No rhonchi, rales, wheeze or retractions 
are auscultated.  Abdomen with normal bowel sounds, 
no hepatosplenomegaly.  Skin shows healing insect 
bites on his lower legs with no impetiginous lesions 
     A CT scan of the patient's chest confirms the 
presence of a 8 x 6 x 8 cm thick walled mass in the 
RML and RLL consistent with an abscess.  He is 
started empirically on clindamycin and cefotaxime.  
Cultures of the abscess fluid isolate non-typable 
Hemophilus influenzae (beta lactamase negative) 
sensitive to ampicillin, cefotaxime, ciprofloxacin and 
trimethoprim/sulfa.  He was continued on clindamycin 
and ampicillin.  He became afebrile within 6 days of 
starting intravenous antibiotics and remained so for the 
rest of his hospital stay.  After two weeks of IV 
antibiotics, he was changed to oral amoxicillin to be 
continued for another two weeks.  His blood culture 
remained negative.

     A lung abscess is defined as an area of necrotic 
material within a thick walled cavity.  The incidence, 
morbidity and mortality of lung abscesses has fallen 
due to improved antibiotic therapy and improved early 
diagnostic capabilities.  Overall, lung abscess remains 
a relatively uncommon disease in the pediatric 

     Risk factors for the development of a lung abscess 
are aspiration, immunodeficiency and hematogenous 
spread.  Aspiration is the most important factor 
predisposing a child to lung abscess (1).  In children, a 
lung abscess may also be a complication of a 
necrotizing pneumonia.  Aspiration occurs in children 
with neurologic disorders, altered mental status, 
impaired cough mechanisms, swallowing dysfunction or 
even foreign body aspiration.  Most lung abscesses 
related to aspiration are polymicrobial and include 
anaerobes.  Hematogenous spread occurs with emboli, 
right sided endocarditis and bacteremia.  
Immunodeficiency in children occurs secondary to 
myeloproliferative disorders, chemotherapy, chronic 
granulomatous disease, hyper IgE syndrome, etc.  
Among pediatric patients, HIV-1 infection has not been 
reported as a risk factor (2).  Additionally, immotile cilia 
disorders and cystic fibrosis can increase the risk for a 
lung abscess.
     A lung abscess can have a well defined fibrotic wall 
that may converge on adjacent structures causing 
compression or dissection of the borders.  Dissection 
into a bronchus results in an air fluid level.  Dissection 
into the plural space forms a purulent effusion and if an 
abscess dissects into the mediastinum, compression of 
large vessels and the heart may occur.
     The organisms associated with lung abscesses 
have evolved as antibiotic therapy and our ability to 
isolate organisms have improved.  In normal children 
with no known underlying disease, the most common 
organisms are anaerobic bacteria, Staph aureus, Strep 
pneumoniae and Strep pyogenes (group A strep). Gram 
negative organisms include non-typable H. influenza, 
Klebsiella and Pseudomonas. Anaerobic organisms are 
the predominate organism isolated from children with 
neurologic disorders (often due to aspiration) and 
include Bacteroides and Peptostreptococcus. 
Mycobacterium tuberculosis should also be considered. 
     Isolating organisms remains difficult.  Bronchoscopy 
is useful only if the abscess has ruptured.  Direct 
needle aspiration can be used if the abscess is near 
the margins of the chest wall and this is aided with CT 
and ultrasound guidance.  Complications of this 
recovery technique include pneumothorax, hemothorax 
and empyema.  Sputum is not reliable, especially if the 
abscess has not ruptured, and it is also very difficult to 
obtain in a child.

Signs and Symptoms
     The most common clinical finding is fever.  
Additional symptoms include cough (productive if the 
abscess has ruptured and foul smelling sputum if the 
organism is anaerobic), dyspnea, chest pain, shoulder 
pain, anorexia and malaise.  Acute onset of symptoms 
is associated with bacterial organisms while subacute 
presentations are typical in patients with tuberculosis 
and fungal abscesses (2).  The course of a lung 
abscess before medical intervention may be 
surprisingly indolent and may last several weeks (1).  
On physical examination, findings are not always 
consistent or specific, especially in children, but include 
tachypnea, decreased breath sounds and rales.

     Chest radiographs usually reveal a well 
circumscribed radiodense cavity with an air fluid level 
that is confirmed with a lateral decubitus views.  The 
width of the air fluid level is usually of equal length on 
both frontal and lateral chest radiographs, and its walls 
are thick with an uneven shaggy appearance (3).  
Atelectasis may be seen if the abscess compresses 
nearby lung parenchyma. Initially the lung abscess 
appears as a solid lesion within the parenchyma (5). 
     Computed tomography is useful in the diagnosis of a 
lung abscess especially in cases where there may be 
multiple or small abscesses, to differentiate an abscess 
from a tumor, and to pinpoint the location of an abscess 
in proximity to other structures.  Classic findings on CT 
include a thick ragged wall, central fluid and 
surrounding parenchymal consolidation.  Distinctive 
features of a lung abscess are well marginated edges, 
greater density of the abscess compared to water and 
contrast enhancement in adjacent tissue (1).
     Ultrasound examination shows a thick irregular wall 
with a blurred outer margin and an oval or round shape 
that forms an acute angle with the chest wall. However, 
with ultrasound, a peripheral lung abscess may contain 
low level echoes and thus can mimic a pleural effusion.  
Voluntary hyperventilation causes symmetric movement 
of the anterior and posterior walls of an abscess cavity, 
while a pleural effusion causes asymmetric movement 
     The location of a lung abscess may be dependent 
on the patient's position especially if aspiration is 
involved.  Supine position at time of aspiration 
commonly results in an abscess located in the upper 
lobes and apical aspects of the lower lobes, while the 
erect position causes basilar portions of the upper 
lobes to be affected.  The right lung is usually affected 
twice as often as the left because of the anatomic 
position of the bronchus (4).
     Blood cultures are positive in less than 10% of 
cases (2).  Leukocytosis and elevated ESR are 
nonspecific.  A PPD should be placed in all patients 
suspected of lung abscess.

Differential Diagnosis
     A lung abscess appearance on a chest radiograph 
can be confused with a pneumatocele, infected 
congenital cyst, loculated empyema, bronchopleural 
fistula or pulmonary sequestration.  Metastatic disease 
from Ewing sarcoma or osteosarcoma can be 
associated with pulmonary lesions with central 

     The treatment of choice for lung abscess is 
conservative medical management, with the length of 
therapy dictated by the patient's clinical course and 
documented radiographic improvement (4).  In most 
cases, the need for surgery is limited to cases of failed 
antibiotic therapy or to an abscess complicated by 
rupture into adjacent tissue (2). 
     Recommended antibiotic regimes include coverage 
against both penicillinase producing Staph aureus and 
anaerobes (5).  If aspiration is suspected or the patient 
is immunocompromised, there should be coverage for 
gram negative organisms.  Patients with cystic fibrosis 
need coverage for Pseudomonas with an 
anti-pseudomonal beta lactam (piperacillin or 
ceftazidime) plus an aminoglycoside.   Intravenous 
antibiotic coverage should continue until the patient is 
nontoxic and afebrile for 48-72 hours at which time oral 
therapy may be considered (2).  Two to three weeks of 
antibiotic treatment are recommended. 
     Surgical intervention includes thoracentesis, guided 
percutaneous needle aspiration and chest tube 
thoracostomy (if the pleural space requires drainage) 
which is recommended if antibiotic therapy fails, a large 
abscess is present or for critically ill or deteriorating 
patients.  In extreme cases, wedge resection or 
lobectomy may be needed. 

     The outcome for pediatric patients is usually very 
good when lung abscesses are uncomplicated, and 
recovery is more rapid than in adults (2).  A study 
focusing on follow-up of patients with primary 
pulmonary abscess who received only antibiotics, 
showed most of them to have normal pulmonary 
function tests, normal growth and no other significant 
lower respiratory tract disease (6).  Chest radiographs 
should be followed but complete resolution may take up 
to 6 months.

     1.  Miller MA, Ben-Ami T, Daum RS.  Bacterial 
Pneumonia in Neonates and Older Children.  In:  
Taussig LM, Landau LI (eds).  Pediatric Respiratory 
Medicine, Mosby, St. Louis, 1999, pp. 644-647.
     2.  Wheeler JG, Jacobs RF.  Lung Abscess.  In:  
Feigin RD, Cherry JD (eds).  Textbook of Pediatric 
Infectious Diseases, fourth edition.  W.B. Saunders, 
Philadelphia, 1998, pp. 301-307.
     3.  Sanford AR, Winer-Muram HT, Ellis JV.  
Diagnostic imaging of pneumonia and its complications 
in the critically ill patient.  Clinics in Chest Medicine 
     4.  Tan TQ, Seilheimer DK, Kaplan SL.  Pediatric 
lung abscess:  Clinical management and outcome.  
Pediatr Infec Dis J 1995;14(1):51-55.
     5.  Emanuel B, Shulman S.  Lung Abscess in Infants 
and Children.  Clin Pediatr 1995,34(1):2-6.
     6.  Asher MI, Spier S, Beland M, Coates AL, 
Beaudry PH.  Primary lung abscess in childhood:  The 
long-term outcome of conservative management.  Am J 
Dis Child 1982;136:491-494.

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Web Page Author:
Loren Yamamoto, MD, MPH
Professor of Pediatrics
University of Hawaii John A. Burns School of Medicine