Organizing pneumonia due to pulmonary non-tuberculosis mycobacteria: a case description and literature analysis
Letter to the Editor

Organizing pneumonia due to pulmonary non-tuberculosis mycobacteria: a case description and literature analysis

Weiwei Gao#, Tianzhen Wang#, Guangchuan Dai, Weiyi Hu, Xiaoli Tang, Shanshan Chen, Yi Zeng, Chunyang Yin

Department of Tuberculosis, The Second Hospital of Nanjing, Nanjing University of Chinese Medicine, Nanjing, China

#These authors contributed equally to this work as co-first authors.

Correspondence to: Yi Zeng, MD; Chunyang Yin, MD. Department of Tuberculosis of Three, Nanjing Public Health Medical Center, Nanjing Second Hospital, No. 1, Kangfu Road, Nanjing 211132, China. Email:;

Submitted Jan 29, 2024. Accepted for publication May 09, 2024. Published online May 24, 2024.

doi: 10.21037/qims-24-193


Infection is the main cause of organizing pneumonia (OP) (1); secondary organizing pneumonia (SOP) due to lung infection is reported to result from various pathogens, such as bacteria (2), fungi (3), and viruses (4). However, descriptions of SOP due to pulmonary nontuberculous mycobacteria (NTM) are rare, and only 10 cases have been reported. Here, we report one case of SOP due to NTM and review the relevant literature.

Case presentation

A 24-year-old man was admitted with a 2-month history of coughing and sputum production. He had no basic diseases or smoking history. Chest computed tomography (CT) showed a partially oval lesion with an incomplete consolidation ring on the anterior surface, central irregular cavity, and posterior surrounding consolidation in the right upper lobe (RUL), without any other lesions (Figure 1). The laboratory investigations including blood analysis of infection index, serum tumor markers, serum autoantibodies, blood cultures, and viral serologies were within the normal limits. Bacterial, mycobacterial, and fungal bronchoalveolar lavage fluid (BALF) samples were negative. He underwent bronchoscopy including in the RUL; however, no definitive sputum acid-fast bacilli (AFB) were detected on culture or polymerase chain reaction (PCR). The metagenomic next-generation sequencing (mNGS) on BALF samples showed Mycobacterium xenopi (the sequence number is 10) which constitutes a very rare and unusual lung infection. According to the NTM diagnostic guidelines (5), NTM can be diagnosed with positive molecular biological detection of BALF. To make a definitive diagnosis, the patient underwent a repeat bronchoscopy with lavage. The strain identification of the lavage fluid showed: Mycobacterium xenopi. The patient was diagnosed with NTM (Mycobacteria xenopi) and received anti-NTM treatment (treatment regimen: clarithromycin 500 mg/day, moxifloxacin 400 mg/day, ethambutol 750 mg/day, rifabutin 450 mg/day). Two weeks later, the patient’s cough was unaccompanied by sputum. According to chest CT, the lesion in the RUL had improved, but a focal rounded area of ground-glass opacity (GGO) surrounded by a complete ring of consolidation in both lower lobes (LL) was observed, a typical manifestation of “reversed halo sign” in LL (Figure 2). A CT-guided lung biopsy in the LL and histopathological examination showed OP without granuloma and a positive AFB (Figure 3). These findings suggested that the progression of lesions in bilateral lungs was SOP due to Mycobacteria xenopi infection; the patient received anti-NTM treatment continually with a combination of prednisolone at a dose of 40 mg/day for 2 weeks. Oral prednisolone was tapered over a period of 6 months and withdrawn, the patient’s symptoms and the opacity improved rapidly, the LL lesion was completely absorbed, and the RUL cavity also improved (Figure 4).

Figure 1 Case 1, initial chest CT showed partially oval lesion with a ring of consolidation on the anterior surface and a central cavity with surrounding consolidation in RUL (A, black arrow), without any other lesions (B-D). CT, computed tomography; RUL, right upper lobe.
Figure 2 Case 1, first follow-up chest CT showed the improvement of the oval lesion and consolidation in RUL with no significant changes of the irregular cavity (A, black arrow). And showed focal rounded area of ground-glass opacity surrounded by a complete ring of consolidation in LL, a typical aspect of “reversed halo sign” (white arrows in B-D). CT, computed tomography; RUL, right upper lobe; LL, lower lobe.
Figure 3 Case 1, pathological findings from LL biopsy with different magnifications (A: ×100; B: ×200; C, ×400) showing organizing pneumonia, non-granulomatous (black arrows, H&E staining). LL, lower lobe; H&E, hematoxylin and eosin.
Figure 4 Case 1, second follow-up chest CT, showing absorption of the irregular cavity in RUL (A, black arrow), and also of the lesions in LL (B-D). CT, computed tomography; RUL, right upper lobe; LL, lower lobe.

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was provided by the patient for publication of this article and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.


To clarify the clinical and radiological features of patients with SOP due to NTM, we reviewed the literature about SOP due to NTM in the databases of PubMed and Wanfang from January 2000 to December 2023 and excluded the laboratory’s basic studies related to SOP secondary to NTM.


Including our one case, 11 cases were identified in the literature, among whom there were 6 males and 5 females, were mainly middle-aged and elderly patients (50–85 years old), and only 1 patient was a young adult patient (24 years old). Among the 11 patients, the main clinical symptoms included dyspnea in 6 cases, both fever and cough in 4 cases, weight loss in 2 cases, and chest pain in 1 case. Most patients had clinical complications with underlying diseases, including 3 patients with chronic obstructive pulmonary disease (COPD), 2 with cardiovascular and cerebrovascular diseases, 2 with surgical history, 1 with autoimmune disease who was taking hormones and immunosuppressants, and 1 with diabetes. In the chest imaging manifestations, there were 3 patients with multiple patchy exudation in 1 lung or both lungs, 3 patients with consolidation, 1 with GGO, 1 patient with honeycomb, and 1 with cavity, among which 2 cases were complicated with pleural effusion. Among the results of etiology examination, 4 cases were Mycobacterium avium, and 4 cases Mycobacterium abscessus, whereas Mycobacterium kansasii, Mycobacterium xenopi, and Mycobacterium gordonae (1 case) were rare. Histopathologic findings revealed that the lesions were distributed in patches with the small airways as the central focus, with patchy filling of alveoli and bronchioles by loose plugs of connective tissue, which was consistent with OP (6). All patients were cured after anti-NTM therapy combined with hormone therapy. The details are summarized in Table 1.

Table 1

Cases of SOP due to NTM infection

Number Sex Age (years) Basic diseases Symptoms Imaging manifestations Pathological findings Type of mycobacterial Treatment Outcome relapse of OP References
1 Female 64 Arterial hypertension, rheumatic mitral valvular disease Fever Micronodules, tree-in-bud pattern, tubular bronchiectasis, and small consolidations with peripheral, basal and bilateral distribution Thickened alveolar septa with lymphocytes and histiocytes and intraluminal plugs, composed of granulation tissue and fibroblasts MAC R + E + CAM + PSL 30 mg/day Cure Fernandes et al. (7)
2 Female 67 Operations Fever and dyspnea Patchy, widely dispersed air-space consolidations and GGO Granulation tissues within alveolar ducts and peripheral airspaces, hyalinous exudates organized within peripheral airspaces, and mild alveolar thickening with edematous changes MAC R + E + CAM + PSL 30 mg/day Cure Hamada et al. (8)
3 Male 73 No Fever Infiltrates with an air bronchogram in the right upper lobe, and ground glass opacities in both lung fields Epithelioid cell granuloma and OP MAC R + E + CAM Cure Nakahara et al. (9)
4 Female 66 No Cough and fever Multiple cavitary nodules OP Abscessus R + CAM Cure Nakahara et al. (9)
5 Female 51 Chronic gastric reflux Cough, chest pain and weight loss Poorly defined nodular opacities in the inferior right upper lobe and a pronounced nodular consolidation in the right mid zone Necrotizing granulomatous inflammation, caseous necrosis and auramine-positive tubercle bacilli in association with an OP Mycobacterium goodii AMK and meropenem ciprofloxacin and doxycycline Cure Waldron et al. (10)
6 Male 59 COPD Dyspnea GGO and consolidation mainly in the left upper lobe Infiltration of inflammatory cells, mainly lymphocytes, and Masson body Abscessus PSL 30 mg/day Cure Watanabe et al. (11)
7 Female 85 RA, hypertension, COPD Cough and dyspnea The right upper, the right lower lobes and bilateral pleural effusions Intra-alveolar young fibrosis tissue and granulocytic infiltrate, consistent with OP Kansasii HRE + PSL 60 mg/day Cure Starobin et al. (12)
8 Female 58 COPD, hypertension, transient ischemic attacks and coronary artery disease Dyspnea, cough, weight loss Cavitating consolidation at the left apex with widespread emphysema and bilateral lower lobe consolidation with air bronchograms TBLB: inflamed, ciliated bronchial epithelium with alveolar spaces obliterated by a polypoid cellular combination of fibroblasts, inflammatory cells and foamy macrophages typical of OP without granulomas MAC HRE + PSL 40 mg/day Cure Jones et al. (13)
9 Female 50 A total gastrectomy for gastric cancer Consolidation, centrilobular shadows, GGO and cavities Non-necrotizing granuloma surrounded by infiltrative lymphocyte-dominant inflammatory cells Abscessus PSL 30 mg/day Cure Okazaki et al. (14)
10 Female 67 Diabetes mellitus and degenerative arthritis Dyspnea and fever Ill-defined multifocal consolidations with bronchial wall thickening and air-bronchogram in both lungs PCNB specimen showed interstitial fibroblast infiltration with collagen deposition and multiple foci of fibroblastic plugs and non-necrotizing epithelioid cell granuloma Abscessus AMK, cefoxitin, and azithromycin + PSL (1 mg/kg/day) Cure Hong et al. (15)
11 Male 24 No Cough Irregular void with surrounding consolidation shadows, “reversed halo sign” in both the lower lobe OP without granuloma and a positive AFB Mycobacterium xenopi H + R + E + PSL
30 mg/day
Cure The present case

SOP, secondary organizing pneumonia; AMK, amikacin; CAM, clarithromycin; COPD, chronic obstructive pulmonary disease; E, ethambutol; GGO, ground-glass opacity; H, isoniazide; MAC, Mycobacterial avium-intracellulare; NTM, non-tuberculous mycobacteria; OP, organizing pneumonia; PCNB, percutaneous needle biopsy; PSL, predonizolone; R, rifampicin; RA, rheumatoid arthritis; TBLB, transbronchial lung biopsy; AFB, acid-fast bacilli.


OP is a pattern of lung-tissue repair after injury. It can be cryptogenic or a response to a specific lung injury and is also observed histopathologically in many diverse clinical contexts (16). OP is divided into 2 types, cryptogenic OP (COP) and SOP, according to the cause of disease (17). In addition to COP form, SOP can be induced by various causes, such as lung infection (3), collagen vascular diseases, drugs, or inhalation (17). As the diagnostic methods for NTM have advanced, the incidence of NTM lung disease is increasing worldwide. However, OP due to mycobacteria NTM has rarely been reported. From 2000 to December 2023, only 10 cases were reported; including the 1 case reported here, the total number of cases is 11.

Clinically, both men and women can experience this disease, although mostly middle-aged and elderly patients are affected. These patients experience constitutional symptoms such as weight loss, fever, malaise, cough and hemoptysis; the clinical symptoms are similar to those of the other respiratory diseases such as COPD, community-acquired pneumonia (CAP), and tuberculosis (TB). Most patients have certain high-risk factors, and the most common diseases are COPD and cardiovascular disease. It has been reported (18) that immunocompromised patients, particularly those with acquired immune deficiency syndrome, have an increased susceptibility to NTM infection and are partly responsible for the increasing prevalence of SOP by NTM infections. The pathogen in NTM-induced OP was Mycobacterium avium-intracellulare (MAC), followed by abscessus, and these are the most prevalent pathogens (9).

During the treatment of case 1, improvements were noticed in the RUL lesions following NTM treatment but also worsening lesions were observed in the bilateral LL. We thought that the worsening lesions in the bilateral LL were due to the progress of the NTM, not drug-induced pneumonitis. Firstly, the drugs used to treat NTM are not common drugs that induce OP (19). Also, Hirama et al. reported that nodules, bronchiectasis, and cavity formation were common radiological features in patients with NTM (20). According to the NTM diagnostic guidelines, the drug remained unchanged throughout the NTM treatment. So, during the process of the treatment in case 1, the drugs used to treat NTM were unchanged, only the prednisolone was gradually decreased. Upon review after 6 months, the patient’s symptoms and the opacity had improved rapidly, the LL lesion was completely absorbed, and the right upper lung cavity had also improved. If drug-induced pneumonitis was a contributing factor, the condition would have worsened and intensified, so OP caused by anti-NTM drugs was also ruled out.

There is currently sufficient literature describing the radiological features of NTM. Some features such as thin-walled cavity and bronchiectasis (21,22) in the middle lobes and the left upper lobe are typical NTM imaging features, as are other such as consolidation, GGO, nodules and “tree-in-bud” pattern and so on (9). However, SOP due to NTM is combined with imaging changes in areas such as near the periphery of LL, and “reversed halo sign” (23), especially during NTM treatment. During treatment of NTM, factors such as lesion progression and the presence of Interstitial lesions in LL should alert the clinician to consider the possibility of SOP by NTM.

The relationship between the NTM pathogens and the onset of SOP is still unknown; the occurrence of pathological reactions in TB is inextricably linked with the host’s response to the invading NTM. Histologically, NTM exhibits granulomas with varying degrees of necrosis (24), but some studies have reported that NTM disease is sometimes accompanied by OP histologically. Yasuharu et al. (9) reported in their study of 98 NTM patients who had undergone a biopsy or surgical resection, 11 patients had OP that was revealed histologically. After excluding 6 patients who had OP-related diseases (idiopathic interstitial pneumonia, rheumatoid arthritis, etc.), the remaining 5 patients were SOP due to NTM. Marchevsky et al. (24) reported in their study of Mycobacteria-positive open-lung biopsy specimens from 40 patients that the specimens of 3 patients with bilateral diffuse infiltrating shadows and no underlying conditions exhibited OP histologically, which all suggested that NTM disease and OP may show no absolute limit in histologically, and it is difficult to clarify the NTM or OP for which they can coexist in histologically. In clinical practice, it is difficult to distinguish the secondary complications solely based on the course of disease; further diagnosis and treatment techniques are still needed to identify the etiology of the disease in clinical practice.

Although the use of corticosteroids in SOP has been and remains controversial, from the literature and our cases, we found that adding corticosteroids to the regimen led to a remarkable improvement, and that complete cure was achieved after corticosteroids were added to anti-TB therapy and the prognosis was good in most of the cases of COP. As the NTM chest disease is increasing worldwide, pulmonologists might have a greater opportunity to observe the NTM lung disease with OP. Additional studies are needed to improve the outcomes of patients with SOP due to NTM; SOP due to NTM should be considered during treatment when antibiotics and/or anti‑mycobacterial drugs are not effective.


SOP due to NTM should be considered during treatment when antibiotics are not effective, especially during the treatment of lesion progression.


The authors wish to acknowledge the included patient, from whom written informed consent was obtained.

Funding: This work was supported by the Nanjing Health Science and Technology Development Special Fund (grant number: M2021073).


Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at All authors report that this work was supported by the Nanjing Health Science and Technology Development Special Fund (grant number: M2021073). The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for publication of this article and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See:


  1. Ketchersid K. A review of organizing pneumonia. JAAPA 2023;36:16-9. [Crossref] [PubMed]
  2. Mull ES, Cohen S, George A, Krivchenia K, Druhan S, Baker PB 3rd, Kopp B. Cryptogenic organizing pneumonia: In the setting of Staphylococcus aureus endocarditis. Pediatr Pulmonol 2023;58:325-7. [Crossref] [PubMed]
  3. Saito Z, Ito T, Imakita T, Oi I, Kanai O, Fujita K. Organizing pneumonia secondary to pulmonary cryptococcosis in immunocompromised patient. Respir Med Case Rep 2024;47:101975. [Crossref] [PubMed]
  4. Tonon CR, Tanni SE, Rocha J, Godoy I, Polegato BF, Pereira FWL, Martins D, Prudente RA, Franco ET, Brizola F, Baldi BG, Okoshi MP. Organizing pneumonia and COVID-19. Am J Med Sci 2023;366:458-63. [Crossref] [PubMed]
  5. Daley CL, Iaccarino JM, Lange C, Cambau E, Wallace RJ Jr, Andrejak C, et al. Treatment of nontuberculous mycobacterial pulmonary disease: an official ATS/ERS/ESCMID/IDSA clinical practice guideline. Eur Respir J 2020;56:2000535. [Crossref] [PubMed]
  6. Cherian SV, Patel D, Machnicki S, Naidich D, Stover D, Travis WD, Brown KK, Naidich JJ, Mahajan A, Esposito M, Mina B, Lakticova V, Cohen SL, Muller NL, Schulner J, Shah R, Raoof S. Algorithmic Approach to the Diagnosis of Organizing Pneumonia: A Correlation of Clinical, Radiologic, and Pathologic Features. Chest 2022;162:156-78. [Crossref] [PubMed]
  7. Fernandes AL, Ferro A, Santos JD, Seabra B. A rare cause of secondary organising pneumonia. BMJ Case Rep 2021;14:e241737. [Crossref] [PubMed]
  8. Hamada K, Nagai S, Hara Y, Hirai T, Mishima M. Pulmonary infection of Mycobacterium avium-intracellulare complex with simultaneous organizing pneumonia. Intern Med 2006;45:15-20. [Crossref] [PubMed]
  9. Nakahara Y, Oonishi Y, Takiguchi J, Morimoto A, Matsuoka K, Imanishi N, Higashino T, Mimura R, Kawamura T, Mochiduki Y. Nontuberculous mycobacterial lung disease accompanied by organizing pneumonia. Intern Med 2015;54:945-51. [Crossref] [PubMed]
  10. Waldron R, Waldron D, McMahon E, Reilly L, Riain UN, Fleming C, O'Regan A. Mycobacterium goodii pneumonia: An unusual presentation of nontuberculous mycobacterial infection requiring a novel multidisciplinary approach to management. Respir Med Case Rep 2019;26:307-9. [Crossref] [PubMed]
  11. Watanabe K, Miyake A, Kaneko T. Secondary organizing pneumonia due to Mycobacterium abscessus lung disease: Case report and review of the literature. Int J Mycobacteriol 2019;8:397-9. [Crossref] [PubMed]
  12. Starobin D, Guller V, Gurevich A, Fink G, Huszar M, Tal S. Organizing pneumonia and non-necrotizing granulomata on transbronchial biopsy: coexistence or bronchiolitis obliterans organizing pneumonia secondary to Mycobacterium kansasii disease. Respir Care 2011;56:1959-61. [Crossref] [PubMed]
  13. Jones RM, Dawson A, Evans EN, Harrison NK. Co-existence of organising pneumonia in a patient with Mycobacterium avium intracellulare pulmonary infection. Monaldi Arch Chest Dis 2009;71:76-80. [Crossref] [PubMed]
  14. Okazaki A, Takato H, Fujimura M, Ohkura N, Katayama N, Kasahara K. Successful treatment with chemotherapy and corticosteroids of pulmonary Mycobacterium abscessus infection accompanied by pleural effusion. J Infect Chemother 2013;19:964-8. [Crossref] [PubMed]
  15. Hong G, Kim DH, Kim YS. Successful treatment of acute respiratory failure in a patient with pulmonary Mycobacterium abscessus infection accompanied by organizing pneumonia. J Thorac Dis 2017;9:E560-4. [Crossref] [PubMed]
  16. King TE Jr, Lee JS. Cryptogenic Organizing Pneumonia. N Engl J Med 2022;386:1058-69. [Crossref] [PubMed]
  17. Krupar R, Kümpers C, Haenel A, Perner S, Stellmacher F. Cryptogenic organizing pneumonia versus secondary organizing pneumonia. Pathologe 2021;42:55-63. [Crossref] [PubMed]
  18. Ellis SM. The spectrum of tuberculosis and non-tuberculous mycobacterial infection. Eur Radiol 2004;14:E34-42. [Crossref] [PubMed]
  19. Radzikowska E, Fijolek J. Update on cryptogenic organizing pneumonia. Front Med (Lausanne) 2023;10:1146782. [Crossref] [PubMed]
  20. Hirama T, Marchand-Austin A, Ma J, Alexander DC, Brode SK, Marras TK, Jamieson FB. Mycobacterium xenopi Genotype Associated with Clinical Phenotype in Lung Disease. Lung 2018;196:213-7. [Crossref] [PubMed]
  21. Garcia B, Wilmskoetter J, Grady A, Mingora C, Dorman S, Flume P. Chest Computed Tomography Features of Nontuberculous Mycobacterial Pulmonary Disease Versus Asymptomatic Colonization: A Cross-sectional Cohort Study. J Thorac Imaging 2022;37:140-5. [Crossref] [PubMed]
  22. Yin H, Gu X, Wang Y, Fan G, Lu B, Liu M, Wang C, Cao B, Wang C. Clinical characteristics of patients with bronchiectasis with nontuberculous mycobacterial disease in Mainland China: a single center cross-sectional study. BMC Infect Dis 2021;21:1216. [Crossref] [PubMed]
  23. Marchiori E, Zanetti G, Irion KL, Nobre LF, Hochhegger B, Mançano AD, Escuissato DL. Reversed halo sign in active pulmonary tuberculosis: criteria for differentiation from cryptogenic organizing pneumonia. AJR Am J Roentgenol 2011;197:1324-7. [Crossref] [PubMed]
  24. Marchevsky A, Damsker B, Gribetz A, Tepper S, Geller SA. The spectrum of pathology of nontuberculous mycobacterial infections in open-lung biopsy specimens. Am J Clin Pathol 1982;78:695-700. [Crossref] [PubMed]
Cite this article as: Gao W, Wang T, Dai G, Hu W, Tang X, Chen S, Zeng Y, Yin C. Organizing pneumonia due to pulmonary non-tuberculosis mycobacteria: a case description and literature analysis. Quant Imaging Med Surg 2024;14(6):4263-4268. doi: 10.21037/qims-24-193

Download Citation