Clusters of small nodules with no confluence

Unilateral Nonconfluent Cluster of Micronodules: Atypical Radiologic Appearance of Pulmonary Tuberculosis in an Immunocompetent Patient

“…Similar findings were subsequently reported in emerging papers prompting that these findings are not entirely exclusive to sarcoidosis, rather it can also occur in cases of tuberculosis [6][7][8][9]. Hence, the respective terms of "cluster of nodules with confluence" and "cluster of nodules without confluence" were proposed to replace the initial aforementioned signs [10]. Heo et al [7] also suggested that "clusters of nodules" be taken as a sign of active tuberculosis even in the absence of other typical features, as all the nodules showed improvement with antituberculous medication despite negative sputum examination for acid-fast bacilli in his patients.…”

“…Similar findings were subsequently reported in emerging papers prompting that these findings are not entirely exclusive to sarcoidosis, rather it can also occur in cases of tuberculosis [ 6 – 9 ]. Hence, the respective terms of “cluster of nodules with confluence” and “cluster of nodules without confluence” were proposed to replace the initial aforementioned signs [ 10 ].…”

“…In these instances, absence of lymphadenopathy and perilymphatic nodules favours tuberculosis compared to sarcoidosis as the underlying pathology [ 2 ]. Another sign which has been described as highly suggestive of active granulomatous process, namely, sarcoidosis and tuberculosis, is the “nodular-reversed halo sign.” The term nodular-reversed halo is used to describe a ring of nodules surrounding an area of ground-glass attenuation [ 10 ]. This should be differentiated from the more widely described “reversed halo sign,” an area of ground glass opacity surrounded by a ring of consolidation, which can be due to many nonspecific causes including organizing pneumonia and fungal infections among others [ 11 ].…”