Our group remained with the diagnosis of a primary lung abscess, partially responding to the antibiotic, but without significant radiological improvement
DISCUSSION
LUNG ABSCESSIs a cirumscribed thick walled cavity in the lung that contain purulent material resulting from suppuration and necrosis of the involved lung parenchyma. Kendig`s text book 98
TYPES
Primary: no predisposing factors
Secondary: underlying predisposing factors
Mark and Turner classification 68
EPIDEMIOLOGY
0.7/100.000
admission/year. Asher et al 82
24
cases /10 years reported by Tumwine 92
21
cases/25years reported by Cowles et al 02
Age:
any, but rare in neonate
More
common in fall and winter
CLINICAL
FEATURES
Tan et al ped Infect dis 95 ,45 cases /11years 82-93
Fever (84%), Cough(53%), Dyspnea (35%), Chest pain(24%), Anorexia (20%),
Purulent sputum (18%), Rhinorrhea (16%), Malaise and lethargy (11%),
other...
Fever,
cough, dyspnea were the commonest presenting symptoms
Tumwine 92 ,M.-H Wu et al 97, Emanuel&Shulman 95
ETIOLOGY
27% S Aureus, Normando et al rev infec dis 90
S.aureus,
group A strept, pseudomonas a, Tumwine E AF med J 92
Anerobes
(27%). Pseudomonas (13%), s aureus (13%), stept p. (7%), H influenza
(7%) Tan et al 95
S
aureus, strept. pneumonia / (s.aureus, E.coli, klebsiella 2nd.LA ) Emanuel/Shulman
95
S
aureus, pneumococci, pseudo.a, klebsiella M.-H.Wu et al 97 s aureus
S.
pneumonia,, pseudomonas A Tseng et al 2001
PREDISPOSING
FACTORS
Pulmonary
Pneumonia
Obstruction of the bronchi
Cystic Fibrosis
Penetrating trauma of the lung
Gastrointestinal
Aspiration
Motility disorder, dysfunction
Tracheoesophageal fistula
Neurologic
impairment
Decreased epiglottic cough reflex
Impaired swallowing mechanism
Dysautonomia
Extrapulmonary
origin
Bacteremia ,emboli
Spread of infection from contiguous sites eg. Liver
Post
surgical
Aspiration
of secretions or pus
Direct
damage to the lung during pulmonary surgery
Immunologic disorder
Steroids
,anti-tumor agents
Brook 93
PATHOPHYSIOLOGY
Inflammation
Necrosis
Progressive fibrosis
Cavitations
The cardinal histopathology: suppurative destruction of lung parynchyma
with central cavitation.
INVESTIGATION
WBC: leukocytosis, neutrophilia, WBC (14-23)
on admission for 18 patients with primary lung abscess. shulman et
al 95
CXR: abscess appears, as solitary thick
wall cavity in the lung, will be clear when it contains air fluid level.
This imaging is very helpful for follow up.
Site:
RLL (right lower lobe) 36%, RUL (right upper lobe) 33%, LLL (left lower
lobe) 27% Tan et al
RLL 50%, LLL33% for primary lung abcess. Em& Shulman
RLL (70%), RUL30% secondary lung abscess. Em& Shulman
LLL 32% RUL 30%,RLL 28%, Sturat et al 91
LLL more common than RUL Tseng et al 2001
CHEST
CT:
In
the evaluation of children with complicated pneumonia, CT often reveals
clinically significant findings not apparent on radiography. Donnelly
et al AJR 98
"CT
chest should be done to all patients pulmonary abscess refractory to
conservative treatment". Cowles et al J ped surg 2002
"CT chest is helpful in determining the optimum site for percutaneous
catheter drainage" Zuhdi et al crit care med 96
Reported
successful treatment of lung abscess under CT guidance in two patients
(neonate, 21/2 years child) Al-salem ped surg 97
BRONCHOSCOPY:
"may be undertaken in children who fail to improve after a week to 10
days of appropriate therapy". Brook 93/McCraken 79
Appropriate intravenous antibiotic therapy alone is recommended as initial
therapy of primary lung abscess in infancy and childhood. However, "if
there is no response to the initial treatment percutaneous aspiration
is advisable before proceeding to more invasive procedures". Bruckheimer
et al ped pul 95
