All the 23 patients with the RHS met the diagnosis of IMD,
while of the 85 patients without the RHS,
44 met the diagnosis of proven/probable IMD and 41 had a diagnosis of “no-IMD”.
Of the 23 patients with the RHS,
2 (9%) were Mucormycosis and 4 (17%) were Invasive Aspergillosis (in one case by A.
Flavus associated with P.
Aeruginosa).
In 11/23 (48%) cases,
the diagnosis was probable IMD (positive GM test: BAL: 8/8; serum: 10/11),
while in 6/23 (26%) cases the diagnosis was highly possible IMD (absence of mycologic evidence,
no alternative diagnosis).
(Table 2 and 3)
Table 2: Table 2. Clinical characteristics and radiological findings.
Table 3: Table 3. RHS prevalence in IMD patients according to neutropenia disease and disease status.
We observed that the lesions with the RHS were associated to other lesions with the halo sign (18/23; 78%).
During the follow-up,
the RHS turned into a nodular dense parenchymal consolidation (18/23; 78%) after 18.5 days on average (range 6-55 days),
but mostly (11/18; 61%) within 17 days (9.1 days on average; range 6-17 days).
An air crescent sign or cavitation was appreciable after 16.5 days on average (range 6-34 days),
and occurred in 12/23 (52%) patients.
We observed two patterns of cavitation,
represented in figure 2: in half of cases (6/12 patients) the air-crescent sign occurred in the peripheral ring-shaped area of consolidation of the RHS (pattern 1),
while in the remaining the cavitation occurred after the complete consolidation of the lesion,
eccentrically (pattern 2).
Fig. 2: Follow up CT scans show the evolution of lesions with the RHS. Pattern 1 (up): the peripheral ring of consolidation enlarge whereas the central area of ground-glass decreases; cavitation appears inside the ring of consolidation. Pattern 2 (down): the upper left lobe lesion with the RHS turn into a nodular dense nodular lesion, then it appears the air-crescent sign (empty arrow)
The duration of radiological follow-up ranged from 3 days (exitus) to 12 months (surviving),
with pulmonary lesions randomly reducing and/or increasing in number and dimension,
and still appreciable for several months after the vanishing of the RHS.