Pulmonary cryptococcosis in asymptomatic immunocompetent hosts

Abstract

Pulmonary cryptococcosis tends to occur commonly in immunocompromized patients. However, as more individuals are undergoing regular medical examinations, the number of cases of pulmonary cryptococcosis detected incidentally in immunocompetent individuals is increasing. The aim of the present study was to evaluate the radiologic manifestations of pulmonary cryptococcosis in immunocompetent patients with no significant symptoms. The clinical records and radiographic findings of 7 immunocompetent subjects with isolated pulmonary cryptococcosis who were diagnosed by pathological examinations, were reviewed. The mean age of patients was 68.4 y (range 58-80 y), and 6 of them were female. The radiographic manifestations in all patients were 1 or more nodules. Computed tomography (CT) demonstrated 22 pulmonary nodules with diameter from 3 mm to 22 mm, and multiple nodules were more frequent than solitary nodules (5 cases versus 2 cases). Axial analysis of patients showed that an involvement of the upper lobe was observed in all patients. Most nodules were well defined and smoothly marginated (21 nodules) and cavitations were infrequent findings (2 nodules). Lymphadenopathies were found in 2 patients. The most common imaging finding of pulmonary cryptococcosis in asymptomatic immunocompetent hosts was the presence of multiple nodules marginated smoothly with upper lobe predominance.

Clinical and radiologic manifestations of pulmonary cryptococcosis in immunocompetent patients and their outcomes after treatment

“…Although most of our patients also had unilobar pulmonary involvement, a finding that was different from previous studies showing multiple lesions, multilobar, or bilateral pulmonary involvement (5-10), and the sizes of the pulmonary nodules, masses and/or consolidations in our patients were more variable, ranging from <1 cm up to 15 cm in greatest diameter. The distinct peripheral, subpleural, and lower lung predominance in the present study was similar only to the findings reported by Fox and Müller (6) and Yang et al (8) but was in contrast to other previous studies showing upper or middle lung predominance mimicking tuberculosis (5,10) or no lobar predilection (4, 9). CT, computed tomography; CXR, chest radiograph; F, female; M, male; NA, not available.…”

“…Calcification within the pulmonary lesion, as shown in one of our cases, is also rare (14,15,17,18). Surrounding groundglass opacity or the CT halo sign, as found in our study, and isolated groundglass opacity (6,(8)(9)(10)(11)17) can be observed. Although centrilobular or satellite nodules have been described (6,8), tree-inbud appearance was observed neither in the present nor in previous studies (6)(7)(8)(9).…”

“…Cavitation and air-filled bronchograms within nodules or consolidation, observed in 58.3% of our cases, have been variably demonstrated in previous studies, ranging from 0% to 42% of cases (4)(5)(6)(7)(8)(9)(10)(11)15). Nonenhanced, low-attenuation areas within the areas of consolidation or masses, previously shown to represent gelatinous collections of large numbers of fungal organisms or rarely ischemic necrosis (12,15,16) were also frequently demonstrated on CT images in our study but have rarely been described (17).…”

“…As with previous studies, pleural effusion is also uncommon, found in less than 10% of cases, and is often small in size (3)(4)(5)(6)(7)(8)(9)(10)18).…”

“…In rare circumstances, the infection occurs in otherwise healthy individuals. According to previous studies from many countries in North America, Europe, and the East (3)(4)(5)(6)(7)(8)(9)(10)(11), most immunocompetent individuals have mild or no clinical symptoms with isolated pulmonary involvement through single or multiple small pulmonary nodules. These findings are somewhat different from the more aggressive clinical and radiographic findings described in isolated case reports among Thai immunocompetent patients (6,(12)(13)(14) and in a study from South America (3).…”