Results
We recruited 38 patients: 21 without signs of infection disease and 17
with signs of infection,23 (60%) male and 15 (40%) female. Diagnosis
was acute leukemia (AL) in 22, brain tumor in 5, lymphoma in 4, sarcoma
in 3 (1 renal sarcoma (RS),1 rhabdomyosarcoma (RMS), 1 osteosarcoma
(OS)), Wilms tumor (WT) in 2, neuroblastoma (NBL) and desmoid
fibromatosis in 1 patient. The mean age was 9.2 years and the median 9
years.
All patients underwent LUS, 16 underwent CXR, 3 chest CT.
Group 1 included 8 cases (21%) of non-infected non-neutropenic
patients, mean age 10.3 years, median 9.5 years.
The 8 LUS were negative. CXR was performed in 4 cases, as part of the
initial evaluation at onset of cancer, and was negative in all cases.
(Table 1)
Group 2 included were 13 (34%) non-infected neutropenic patients, the
mean age was 7.1 years, the median age 5 years; in only one case,
ultrasonography revealed rare B lines and bilaterally subpleural air
bronchograms; according to CXR images these findings were probably
related to leukemic infiltrates present at the onset of the disease. In
this group there was an agreement between ultrasound and CXR of 83%.
Particularly, the finding on x-ray of a nuanced hilar thickening, in a
patient with onset of acute lymphoblastic leukemia, afebrile and with
normal CRP, was not evidenced on LUS. (Table 1)
Group 3 recluted 7 infected non-neutropenic patients (19%), mean age 11
years, median 9 years. Three patients (42%) presented with respiratory
symptoms; two initially asymptomatic patients subsequently presented
respiratory symptoms. (Table 1) Of the seven LUS performed, 5 were
positive and 2 were negative.
6 CXR were performed: 4 were negative and 2 were positive. In case 25 a
second CXR was repeated after the onset of respiratory symptoms and
turned out positive.
Between the ultrasound examinations and the radiographic examinations
there was agreement in 67% of cases. In this group, 3 pathological
chest CT scans were performed with 100% concordance LUS. In one of the
three cases (33%) chest CT was discordant with CXR.
LUS images were pathological, in the absence of initial respiratory
symptoms, which appeared in the following 24 hours with a rapid decline
in lung function in two cases. In these two cases (patient 25 and 26)
the negativity of the radiographic examination can be considered as
false negative, in fact the patients presented both pathological
ultrasound images and afterwards clinical symptoms compatible with lung
infection. In both cases, for clinical worsening and the onset of
respiratory symptoms, CXR (patient 25), repeated 4 days later, and chest
CT (patient 26) performed one day after the CRX execution, were positive
for pneumonia. (Fig. 1)
Group 4 included 10 infected neutropenic patients (26%), mean age 8.5
years, median 10 years. We found respiratory symptoms only in 1 case.
The results of laboratory and instrumental tests are shown in Table 2.
In 50% of cases the LUS was found to be pathological.
None of the 10 patients underwent a CXR and in no case was it necessary
to perform a chest CT for the benign course of the infection.
Between group 3 and 4, 10 patients presented positive LUS and underwent
ultrasound follow-up at three and seven days from first LUS showing
resolution of the pathological signs in 6 cases. In the 4 cases with
persistent pathological images at day seven, a further LUS was performed
after 1 month, with resolution of pneumonia in all cases.