Pulmonary Nocardiosis in Fine-Needle Aspiration Cytology Smears: Report of Four Cases Sudha Sharma, MBBS, MD, 1 Priya Singh, MBBD, MD, 1 Rashi Garg, MBBS, MD, 2 and Pranab Dey, MBBS, MD, MIAC, FRCPATh 2 * Nocardia has been recognized as a significant opportunistic pathogen in organ transplant patients; however, it is an uncom- mon pathogen in immunocompetent patients. It may mimic other infectious diseases both clinically and radiologically. We report four cases of pulmonary nocardiosis in three immunocompro- mised and one immunocompetent patients on fine-needle aspira- tion cytology (FNAC). Two patients presented with lung consolidation while two had cavitatory lesions. FNAC smears showed inflammatory cells composed of polymorphs and histio- cytes along with necrosis. Occasional epithelioid cell granuloma was seen in one case. Modified Ziehl–Neelsen (ZN) stain was performed which highlighted long slender filamentous branching organisms conforming to the morphology of Nocardia. Thus, a suspicion for nocardiosis should be kept while assessing cyto- logic material especially in immunocompromised individuals. The diagnosis can be confirmed by special stains and culture studies; however, a high index of clinical suspicion is required so that appropriate culture media can be used for high diagnos- tic yield. FNAC is of help in providing immediate and accurate diagnosis of nocardiosis, thus helping in appropriate medical management. Diagn. Cytopathol. 2016;44:347–350. V C 2016 Wiley Periodicals, Inc. Key Words: Nocardia; FNAC; lung Introduction Nocardia are aerobic gram-positive bacteria of the order Actinomycetales. Nocardiosis usually occurs as an oppor- tunistic infection in immunocompromised patients but can also affect non-immunocompromised hosts. 1 It mimics pulmonary tuberculosis both clinically and radiologically and is sometimes wrongly treated with antituberculosis drugs. 2 The diagnosis is often missed on routine stains as these bacilli have very delicate filaments that stain lightly with routine stains and are obscured by the accompanying inflammatory exudates. 3 The infection responds to long- term antimicrobial therapy with trimethoprim–sulfame- thoxazole, imipenem, or amikacin, and thus an accurate diagnosis is essential. 4 A high degree of suspicion in a proper clinical setting with appropriate special stains helps in the diagnosis. We report a series of four cases of pulmonary nocardiosis in three immunocompromised and one immunocompetent patient, diagnosed by modified Ziehl–Neelsen (ZN) staining of the material obtained by fine-needle aspiration cytology (FNAC) of lung lesions. Case Reports In each case, written consent was taken before performing ultrasound- and CT scan-guided FNAC. There was no ethical violence in this article and the study is retrospec- tive collection of cases diagnosed in last 6 months of FNAC procedure. The detailed description of all four cases has been highlighted in Table I. Case 1 A 55-year-old-female patient—known case of systemic lupus erythematosis, on steroids—presented with history of fever and rash. Contrast-enhanced CT scan of chest was performed which revealed large patchy areas of con- solidation in both lower lobes of lungs. Clinical suspicion was that of an infectious etiology and a possibility of tuberculosis was suggested. Ultrasound-guided FNAC was done from the left lower lobe which yielded necrotic 1 Department of Pathology, Postgraduate Institute of Medical Educa- tion and Research, Chandigarh, India 2 Department of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India Ethical justification: Written consent was taken before performing USG and CT scan-guided FNAC. There was no ethical violence in this article and this study is a retrospective collection of cases diagnosed in last 6 months. The identity of the patients was kept in secret. External grant: No financial or other support was taken. *Correspondence to: Dr Pranab Dey, MD, MIAC, FRCPath; Depart- ment of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India. E-mail: deypranab@hotmail.com Received 31 October 2015; Revised 14 December 2015; Accepted 21 December 2015 DOI: 10.1002/dc.23429 Published online 13 January 2016 in Wiley Online Library (wileyonlinelibrary.com). V C 2016 WILEY PERIODICALS, INC. Diagnostic Cytopathology, Vol. 44, No 4 347