Transcript Cellular and combined immunodeficiencies

IMAGING OF CHEST INFECTIONS IN
IMMUNOCOMPROMISED CHILD
F.AKID, H.FOURATI, E.DAOUD, I.AMMAR, W. FEKI, L.SFAIHI*, M.HACHICHA*, Z.MNIF
Radiology service, Hedi Chaker Hospital Sfax, Tunisia
*Pedaitrics service, Hedi Chaker Hospital Sfax, Tunisia
PEDIATRICS : PD 14
Introduction:
 The population of children afflicted with primary or
secondary immunodeficiencies is in evolution
 This complex and varied population is at high risk for
pulmonary complications related to both their
underlying disease state and to various treatment
regimes
 Our purpose
is to describe the main imaging
appearances of the common infectious complications
in immunocompromised children and to emphasize
on difficulties in the interpretation of chest imaging in
these cases.
Materials and methods:
 Didactic poster, showing through a serie explored
in our service different aspects of lung infections in
children with various immunodeficient states
 All patients underwent a chest radiograph and a
chest CT scan.
Results:
Case 1:
A 4-year-old boy with IL12 deficiency
A
B
C
D
(A): Frontal chest radiograph demonstrates left upper lobe pneumonia
(B, C and D): Axial images from an intravenous contrast-enhanced chest
CT, soft-tissue algorithm, show large mediastinal abscesses (arrows), which
were drained revealing Mycobacterium tuberculosis. This child also had
multiple left lobe lung abscess (arrow head) and a sternal osteolysis.
Case 2:
A 10-year-old boy with chronic granulomatous disease
A
B
C
D
(A): Frontal chest radiograph demonstrates subtle diffuse interstitial
opacities caused by Pneumocystis carinii pneumonia.
(B,C): Axial images, lung algorithm, from a CT examination through the
chest demonstrates scattered bilateral ground glass and interstitial
opacities.
(D): Mosaic appearance with alternating of hyperdense and hypodense
areas
Case 3:
A 4-year-old boy with acute myeloid leukemia
A
B
(A,B and C) Axial images from a chest CT, lung algorithm, shows
centrilobular micronodules surrounded by a ground glass
appearance mainly at the right lower lobe caused by a candidiasis.
C
Case 4:
A 6-year-old boy with chronic granulomatous disease
A
B
C
(A):Frontal Chest Radiograph shows hazy airspace consolidation in the
left lung with air bronchogram. Enlargement of soft tissues and
interruption of the left costal third anterior arc caused by an aspergillosis
(B and C):Consolidation in the left upper lobe with chest wall invasion. A
small consolidation in the middle lobe.
Case 4:
A 6-year-old boy with chronic granulomatous disease
A
B
(A and B):Control CT after 5 months: the pneumonia has not
resolved. The chest wall invasion has occasioned parietal
abscess (arrow) in front of the consolidation.
Discussion:
 The immunodeficiency states in children may be
sub-divided into two major groups:
 Congenital or primary immunodeficiencie
 Acquired or secondary immunodeficiencie
Discussion:
Specific thoracic complications vary according
to the child’s underlying immune status and specific
treatment protocols. As such, the type of infection or
other disease states encountered depends on :
 The child’s type of immunologic abnormality
 Severity of immunologic deficit
 Therapeutic interventions
 Environmental exposures
Primary immunodeficiencies
Humoral immunodeficiencies:
 The
most commonly encountered type of primary
immunodeficiency, accounting for over 70% of all primary
immunodeficiencies
 Characterized by defective antibody production causing
increased susceptibility of affected individuals to recurrent
pyogenic infections, particularly caused by encapsulated
bacteria, such as Haemophilus influenzae, Streptococcus
pneumoniae,and Staphylococci
Primary immunodeficiencies
Humoral immunodeficiencies:
 Typical manifestations include recurrent pneumonia, otitis
media, sinusitis, and sepsis
 Radiographically, children classically demonstrate thoracic
abnormalities related to recurrent pulmonary infections
including bronchiectasis, bronchial wall thickening, and
atelectasis
 Bronchiectasis is commonly located in the middle and lower
lobes with an upper lobe distribution being unusual
Primary immunodeficiencies
Cellular and combined immunodeficiencies:
 Patients
with cellular immunodeficiencies have increased
susceptibility to disseminated viral and opportunistic infections.
 Progressive pneumonia often occurs because of respiratory syncytial
virus, parainfluenza 3 virus, Pneumocystis carinii, varicella, or
cytomegalovirus
 Disorders
include DiGeorge syndrome and severe combined
immunodeficiency (SCID)
 SCID syndrome is characterized by the absenceof both T- and B-cell
function
Primary immunodeficiencies
Cellular and combined immunodeficiencies:
 Chest radiographs may demonstrate narrow upper mediastinal
contour and retrosternal lucency caused by absence of thymic
tissue .
 Pulmonary complications include recurrent pneumonias cause
by P carinii, parainfluenza, respiratory syncytial virus,
adenovirus, cytomegalovirus, or bacterial organisms.
 Pneumocystis
pneumonia typically manifests as diffuse
interstitial infiltrates,which may progress to alveolar infiltrates
Primary immunodeficiencies
Partial combined immunodeficiency syndromes:
 Partial combined immunodeficiency syndromes encompass a
spectrum of disorders with varied clinical manifestations.
 These diseases include :
 Wiskott-Aldrich syndrome,
 Cartilage-hair hypoplasia,
 Ataxia-telangiectasia,
 Purine-nucleoside phosphorylase deficiency,
 X-linked lymphoproliferative disease
Primary immunodeficiencies
Partial combined immunodeficiency syndromes:
 Children with partial combined immunodeficiencies have
increased susceptibility to recurrent sinopulmonary infections
 Children afflicted with Wiskott-Aldrich syndrome and ataxia-
telangiectasia have the highest malignancy rates of all primary
Immunodeficiencies
 Patients with ataxia-telangiectasia are highly susceptible to
radiation-induced malignancies and use of ionizing radiation
for evaluation of these children should beperformed
judiciously
Primary immunodeficiencies
Disorders of phagocytic cells and adhesion molecules:
 Chronic granulomatous disease is the most common
phagocytic disorder, occurring in approximately 1 in 125,000
live births
 this disorder is seen most commonly in males
 These children develop recurrent infections, commonly with
catalase-positive bacteria, such as Staphylococcus aureus or
fungi including Aspergillus, caused by defective intra-cellular
killing by neutrophils .
 This disease usually presents before 1 year of age with
pulmonary infections occurring most frequently
Primary immunodeficiencies
Disorders of phagocytic cells and adhesion molecules:
 Chest radiographs or chest CT typically demonstrate
lymphadenopathy, recurrent pneumonia, and pleural
thickening .
 The radiographic manifestations of Aspergillus vary but
segmental or lobar infiltrates, nodular opacities, and cavitation
are typical .
 Recurrent pneumonias and pulmonary abscesses are common
 Other
thoracic manifestations include
osteomyelitis, and chest wall abscesses
lymphadenitis,
Secondary immunodeficiencies:
AIDS :
 Most of these cases are acquired through vertical transmission
from HIV-positive mothers
 Pulmonary infections are a major source of morbidity and
mortality in children with AIDS.
 Fifty percent of children who die from AIDS do so as a result of
complications from pulmonary disease
 These children are at risk for many opportunistic infections,
such as P carinii pneumonia (PCP) and mycobacterial
pneumonia, acute bacterial pneumonias are common
Secondary immunodeficiencies:
AIDS :
 The typical radiographic appearance of PCP includes increased
interstitial markings, which spread from an initial perihilar
distribution to the periphery. Alveolar opacities often
accompany progression of interstitial disease
 Adenopathy and pleural effusions are rarely seen in association
with PCP
 Chest CT in children with PCP typically demonstrates
peribronchial cuffing, patchy consolidation, ground glass
opacity and parenchymal cysts
Secondary immunodeficiencies:
AIDS :
 Children with AIDS are also susceptible to mycobacterial
infections, although the incidence is less common than in the
adult population with AIDS.
 The
radiographic appearance mimics that seen in
immunocompetent children with hilar adenopathy and lobar
collapse or consolidation
 Miliary tuberculosis in children with AIDS, however, is
distinctly unusual
Secondary immunodeficiencies:
Bone marrow and stem cell transplantation :
 The temporal sequence of events after BMT is predictable with
initial profound neutropenia lasting from 2 to 4 weeks
 Local lung defense mechanisms are also impaired after BMT
for up to 12 months
 Early infectious complications after BMT are most frequently
caused by bacteria and fungi, most commonly gram-negative
organisms and Aspergillus
 Chest
radiographs may show a classic focal or lobar
consolidation, although atypical features are not uncommon
Secondary immunodeficiencies:
Bone marrow and stem cell transplantation :
 Children are also at increased risk of viral infections, most
importantly respiratory syncytial virus, herpes simplex virus,
adenovirus, and varicella
 Radiographic findings are nonspecific but may include marked
pulmonary hyperinflation and bilateral perihilar opacities,
which coalesce into diffuse airspace disease
 Fungal pneumonias in children who have undergone BMT are
typically caused by Aspergillus or Candida species.
Secondary immunodeficiencies:
Bone marrow and stem cell transplantation :
 Angioinvasive pulmonary aspergillosis is reported to occur in
approximately 4% of children after BMT
 Late
sequellae of BMT differ from the complications
encountered early in the posttransplant period and include
infections and bronchiolitis obliterans, diffuse alveolar
damage, lymphocytic interstitial pneumonitis, and relapse of
the underlying disease
Secondary immunodeficiencies:
Solid organ transplantation:
 The thorax is a common site of infectious complications to the
pediatric transplant recipient after solid organ transplantation
 Long-term immunosuppressive therapy increases the risk of
infection and the risk of neoplasms including various
lymphoproliferative disorders
 Children who have undergone renal transplantation are highly
susceptible to infection with cytomegalovirus
 P carinii pneumonia (PCP) and Aspergillus infection are also
common infections after renal transplantation
Secondary immunodeficiencies:
Patients with cancer:
 Children undergoing chemotherapy and radiation therapy for
malignancy are also at increased risk for pulmonary
complications
 Children who are predominately neutropenic as a result of
chemotherapy are at risk for gram-negative infections, such as
Pseudomonas aeruginosa and Klebsiella species, and grampositive infections with such organisms as S aureus
Secondary immunodeficiencies:
Patients with cancer:
 Children with leukemia are at increased risk for infection with
S pneumoniae, H influenzae, and gram-negative bacilli
 Children with T-cell defects related to high-dose corticosteroid
treatment or Hodgkin’s disease are more likely to develop viral
or fungal infections
Conclusion:
 Combination
of
clinical knowledge and
radiological features is useful to understand the
pathologic pulmonary changes encountered in the
immunocompromised patients