Silicosis is an irreversible respiratory condition resulting from exposure to respirable crystalline silica. Presently, the prevalence of silicosis remains significant, with treatment options being notably limited. Miltefosine, an inhibitor of phosphatidylcholine synthesis, has been found to possess both anti-inflammatory properties and inhibitory effects on immune cell infiltration in the airways. The present study evaluated the therapeutic potential of miltefosine in silica-associated pulmonary fibrosis. We established mouse models via airway administration of silicon dioxide (SiO2) (200 mg/kg). Different type of pulmonary fibrosis (PF) model including bleomycin (BLM) and Fluorescein Isothiocyanate (FITC) were then utilized to examine the therapeutic effect of Miltefosine. Oral miltefosine exhibits significant therapeutic efficacy against pulmonary fibrosis induced by SiO2, as well as other etiologies such as BLM and FITC. This efficacy is evidenced by significant reductions in fibrotic markers and pathological staining characteristics post-treatment, paralleling the antifibrotic effects observed with pirfenidone. In cellular experiments, primary fibroblasts from idiopathic pulmonary fibrosis (IPF) patients and healthy controls were utilized for in vitro therapeutic evaluation and mechanistic exploration. Miltefosine was found to attenuate fibrosis progression by inhibiting fibroblast activation, proliferation, and migration capabilities, while promoting apoptosis. Mechanistically, miltefosine exerts its effects by inhibiting Akt activation, which in turn prevents mTOR phosphorylation. Additionally, human precision-cut lung slices (hPCLS) was employed to evaluate the efficacy of miltefosine in treating pulmonary fibrosis induced by a cocktail of agents, and miltefosine significantly reduced its collagen deposition. Our results imply that miltefosine can alleviate SiO2-induced pulmonary fibrosis in murine models and attenuate fibrosis progression in hPCLS by inhibiting fibroblast activation through the suppression of Akt activation and mTOR phosphorylation.

BackgroundPulmonary fibrosis (PF) is an irreversible and lethal lung disease characterized by progressive scarring lacking safe and effective treatment options. Recent studies have underscored the role of macrophage polarization in fibrotic progression, yet the role of kynurenine (Kyn), a metabolite of tryptophan (Trp), in macrophages during PF progression remains elusive.MethodsLiquid Chromatography-tandem Mass Spectrometry (LC-MS) analysis was used to detect tryptophan metabolism changes in the serum of PF patients and control subjects. Macrophage-specific Ido1 or Ahr deletion mice was utilized to explored the role of Kyn in the bleomycin-induced fibrotic mouse model and ChIP sequence was employed to elucidate the mechanism by which Kyn inhibits pro-fibrotic macrophage activation.ResultsWe identified Kyn, Trp levels and Kyn/Trp ratio (KTR) were notably elevated in the serum of patients with different types of PF and these alterations were inversely correlated with lung function. Although such elevation might appear pathogenic, our functional studies demonstrate that Kyn exerts protective effects in PF, akin to brain natriuretic peptide in heart failure. Macrophage-specific deletion of Ido1 or aryl hydrocarbon receptor (AhR, the receptor of Kyn) exacerbated bleomycin-induced PF, while exogenous Kyn supplementation mitigated disease severity. Mechanistically, Kyn bound to the AhR, facilitating its nuclear translocation, where it promoted Slc39a10 transcription to increase the intracellular levels of zinc ion, thereby inhibiting profibrotic macrophage differentiation. Intriguingly, pirfenidone was noted with high potency to suppress Kyn production and our studies demonstrated that administration of Kyn along with pirfenidone effectively enhanced the therapeutic efficacy against PF.ConclusionsIn summary, these findings reveal a previously unrecognized Kyn-AhR-SLC39A10-Zn2+ signaling axis that governs macrophage polarization in PF, and unveiled the importance of Trp metabolism in PF pathogenesis, which could be novel therapeutic strategies against PF.

BACKGROUND:Idiopathic pulmonary fibrosis (IPF) is a progressive, age-related lung disease with few modifiable risk factors. While healthy dietary patterns have been associated with reduced risk of chronic diseases, their impact on IPF remains unclear. This study investigated the relationship between adherence to healthy dietary patterns and incident IPF and explored whether phenotypic age acceleration mediates this association. METHODS:We analyzed 196,473 participants from the UK Biobank. Dietary intake was assessed via repeated 24 -h recall questionnaires, and adherence scores were calculated for the DASH, MEDAS, and MIND dietary patterns. Cox proportional hazards models were used to estimate the association between dietary scores and incident IPF. Mediation analysis was conducted to examine the role of phenotypic age acceleration. RESULTS:During a median follow-up of 12.4 years, 516 IPF cases were identified. Higher adherence to all three dietary patterns was significantly associated with a reduced risk of IPF. In fully adjusted models, hazard ratios for the highest vs. lowest quartiles were 0.75 (95% CI: 0.59-0.95) for DASH, 0.53 (0.37-0.75) for MEDAS, and 0.66 (0.51-0.86) for MIND. Phenotypic age acceleration partially mediated these associations. CONCLUSIONS:Higher dietary scores were associated with a lower risk of incident IPF, partially mediated by reduced phenotypic age acceleration. These findings suggest that promoting healthy eating habits may contribute to reducing age-related lung disease burden in older adults.

Background: Pulmonary fibrosis (PF), the end-stage manifestation of interstitial lung disease, is defined by excessive extracellular matrix deposition and alveolar destruction. Activated fibroblasts, the primary matrix producers, rely heavily on dysregulated glucose metabolism for their activation. While Salt Inducible Kinase 2 (SIK2) regulates glycolytic pathways in oncogenesis, its specific contributions to fibroblast activation and therapeutic potential in PF pathogenesis remain undefined. This study elucidates the functional role of SIK2 in PF and assesses its viability as a therapeutic target. Methods: SIK2 expression/localization in fibrosis was assessed by Western blot and immunofluorescence. Fibroblast-specific Sik2 KO mice evaluated effects on bleomycin-induced fibrosis. SIK2’s role in fibroblast activation and glucose metabolism impact (enzyme expression, metabolism assays, metabolites) were tested. SIK2 inhibitors were screened and evaluated therapeutically in fibrosis models. Results: It demonstrated significant SIK2 upregulation, specifically within activated fibroblasts of fibrotic lungs from both PF patients and murine models. Functional assays demonstrated that SIK2 is crucial for fibroblast activation, proliferation, and migration. Mechanistically, SIK2 enhances fibroblast glucose metabolism by increasing the expression of glycolysis-related enzymes. Additionally, this study demonstrated that the SIK2 inhibitor YKL06-061 effectively inhibited PF in both bleomycin and FITC-induced PF mouse models with the preliminary safety profile. Furthermore, we identified a novel therapeutic application for the clinically approved drug fostamatinib, demonstrating it inhibits fibroblast activation via SIK2 targeting and alleviates PF in mice. Conclusions: Our findings highlight SIK2 as a promising therapeutic target and provide compelling preclinical evidence for two distinct anti-fibrotic strategies with significant potential for future PF treatment.

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease of unknown etiology with poor prognosis and limited therapies. OTS514, a PBK inhibitor, has been implicated in suppressing tumor progression by modulating various cellular biological processes. Nonetheless, the potential impact of PBK and OTS514 on IPF have yet to be elucidated. PBK expression and distribution in IPF and control lung tissues were analyzed by Western blot, RT-PCR, and immunofluorescence. Then, the bleomycin (BLM) -induced mouse model and human precision-cut lung slices (HPCLS) were utilized to detect the antifibrotic effects of the OTS514. Primary lung fibroblasts derived from both control and IPF patients were further employed to uncover the underlying mechanisms of PBK. Our study demonstrated that PBK expression was markedly elevated in IPF patients and exhibited a negative correlation with lung function. Remarkably, the administration of OTS514 significantly mitigated collagen deposition and lung tissue remodeling in the BLM-induced mouse model. Additionally, OTS514 also exserted a pronounced antifibrotic effect in HPCLS, as evident by downregulation of fibrotic related markers expression (α-SMA, Collagen 1 and Fibronectin) and pathological manifestations. In vitro experiments demonstrated that the inhibition of PBK suppressed fibroblast differentiation and migratory capacity, reduced the proliferation rate, and promoted apoptosis. Mechanically, we discovered that the protective effect of OTS514 in vivo and vitro was closely dependent upon the endoplasmic reticulum stress pathways. Collectively, our data underscores the potential of OTS514 as an antifibrotic strategy by attenuating fibroblast-to-myofibroblast transition. Furthermore, the administration of OTS514 manifested no adverse effects in mouse model.

Pulmonary fibrosis (PF) is an irreversible, progressive, chronic and fatal interstitial lung disease with limited therapeutic options. Dehydrocorydaline (DHC), derived from the traditional Chinese medicinal plant Corydalis yanhusuo, has exhibited a variety of pharmacological properties. Nevertheless, the potential function and mechanism of DHC in the management of PF have yet to be elucidated. To evaluate the therapeutical efficacy of DHC in different PF models and elucidate its underlying mechanism. A well-established Bleomycin-induced PF mouse model and human precision-cut lung slices (hPCLS) following fibrosis-inducing cocktail stimulation were employed. The antifibrotic effects of DHC on PF were measured by histopathological manifestation, immunofluorescent staining and expression levels of fibrosis related markers. Human primary pulmonary fibroblasts (HPFs) were used to explore the impact of DHC on fibroblast function and the underlying mechanism. Here, we demonstrated that DHC exhibited a therapeutic efficacy in Bleomycin-induced PF mouse model with a dose dependent, as well as in hPCLS after fibrosis-inducing cocktail stimulation, as evidenced by histopathological staining, decrease of Fibronectin, Collagen 1 and α-SMA expression. Additionally, in vitro experiments indicated that DHC effectively suppressed fibroblast to myofibroblast transition, but had no significant effect on the proliferation and migration of fibroblast. Mechanistic studies revealed that the inhibitory effect of DHC on fibroblast activation was dependent on the endoplasmic reticulum stress, thereby inhibiting TGF-β/SMAD signal pathway. Our study implied that DHC hold a promise therapeutic approach against PF by suppressing fibroblast activation. The safety and efficacy of DHC have been preliminary demonstrated in a mouse model.

Abstract Background Silicosis represents a paramount occupational health hazard globally, with its incidence, morbidity, and mortality on an upward trajectory, posing substantial clinical dilemmas due to limited effective treatment options available. Trigonelline (Trig), a plant alkaloid extracted mainly from coffee and fenugreek, have diverse biological properties such as protecting dermal fibroblasts against ultraviolet radiation and has the potential to inhibit collagen synthesis. However, it’s unclear whether Trig inhibits fibroblast activation to attenuate silicosis-induced pulmonary fibrosis is unclear. Methods To evaluate the therapeutic efficacy of Trig in the context of silicosis-related pulmonary fibrosis, a mouse model of silicosis was utilized. The investigation seeks to elucidated Trig's impact on the progression of silica-induced pulmonary fibrosis by evaluating protein expression, mRNA levels and employing Hematoxylin and Eosin (H&E), Masson's trichrome, and Sirius Red staining. Subsequently, we explored the mechanism underlying of its functions. Results In vivo experiment, Trig has been demonstrated the significant efficacy in mitigating SiO2-induced silicosis and BLM-induced pulmonary fibrosis, as evidenced by improved histochemical staining and reduced fibrotic marker expressions. Additionally, we showed that the differentiation of fibroblast to myofibroblast was imped in Trig + SiO2 group. In terms of mechanism, we obtained in vitro evidence that Trig inhibited fibroblast-to-myofibroblast differentiation by repressing TGF-β/Smad signaling according to the in vitro evidence. Notably, our finding indicated that Trig seemed to be safe in mice and fibroblasts. Conclusion In summary, Trig attenuated the severity of silicosis-related pulmonary fibrosis by alleviating the differentiation of myofibroblasts, indicating the development of novel therapeutic approaches for silicosis fibrosis.

The bleomycin-induced pulmonary fibrosis mouse model is commonly used in idiopathic pulmonary fibrosis research, but its cellular and molecular changes and efficiency as a model at the molecular level are not fully understood. In this study, we used spatial transcriptome technology to investigate the cellular and molecular changes in the lungs of bleomycin-induced pulmonary fibrosis mouse models. Our analyses revealed cell dynamics during fibrosis in epithelial cells, mesenchymal cells, immunocytes, and erythrocytes with their spatial distribution available. We confirmed the differentiation of the alveolar type II (AT2) cell type expressing Krt8, and we inferred their trajectories from both the AT2 cells and club cells. In addition to the fibrosis process, we also noticed evidence of self-resolving, especially to identify possible self-resolving related genes, including Prkca. Our findings provide insights into the cellular and molecular mechanisms underlying fibrosis resolution and represent the first spatiotemporal transcriptome dataset of the bleomycin-induced fibrosis mouse model.

To the Editor: Coronavirus disease 2019 (COVID-19), which broke out in 2019, has become a global pandemic. Similar to severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003, SARS-CoV-2 could cause acute lung injury and cytokine storms characterized by the increased interleukin (IL)-8, IL-6, and tumor necrosis factor α (TNF-α).[1] Perspective studies in those survivors from the severe acute respiratory syndrome (SARS) epidemic in 2003 revealed that those SARS patients manifested varying degrees of pulmonary interstitial fibrosis.[2] Similarly, patients with severe COVID-19 are also featured by the diffuse alveolar damage along with alveolar interstitial fibrosis.[3] Pirfenidone (Beijing Contini Pharmaceutical Co., Ltd, Beijing, China) can inhibit the biological activity of fibroblasts and reduce matrix collagen deposition, prevent inflammasome activation and limit oxidative stress responses, supporting a therapeutic potential against idiopathic pulmonary fibrosis (IPF).[4] Given the presence of alveolar interstitial fibrosis in severe COVID-19 patients and the effect of pirfenidone on anti-inflammatory responses and anti-fibrosis, we hypothesized that pirfenidone can play a positive role in COVID-19 patients, thereby reducing the incidence of complications following SARS-CoV-2 infection. We thus conducted a clinical trial to assess the potential therapeutic effect of pirfenidone on severe COVID-19 patients. This trial (ClinicalTrials.gov number: NCT04282902; Chinese Clinical Trial Register number: ChiCTR2000030333) was conducted from January 31 to March 3, 2020 at Tongji Hospital (Headquarters Campus, Caidian Campus, Guanggu Campus) and Jingzhou Hospital (Hubei, China), which was approved by the Institutional Review Board of Tongji Hospital and Jingzhou Hospital. Male and non-pregnant female COVID-19 patients (≥18 years) with a blood oxygen saturation (SaO2) of 94% or less, and a ratio (PaO2:FiO2) of ambient air or partial oxygen pressure (PaO2) to inhaled oxygen (FiO2) of 300 mmHg or less, were eligible for the study. The exclusion criteria were: patient disinterest in the study; the presence of conditions that did not allow for safe compliance, including hypersensitivity to pirfenidone; liver disease (eg, alanine aminotransferase levels >5 times the upper limit of the normal range [ULN] or aspartate aminotransferase levels >5 times ULN; contraindications of pirfenidone and pre-existing interstitial lung disease [ILD]). Consecutive patients, who meet the inclusion criteria, were randomly assigned in a 1:1 ratio to pirfenidone (200 mg, three times daily for the first two days and 400 mg, three times daily thereafter) plus standard therapy or standard therapy alone. Pirfenidone was given through a nasogastric tube in patients who were unable to swallow. The primary end-point was the absolute changes from baseline in the total score on the King's Brief Interstitial Lung Disease (K-BILD) questionnaire at the 4th week, a change between 4 and 8 points has been suggested to represent a meaningfulchange. Secondary endpoint was the absolute change in computed tomography (CT) values, the total CT value was the sum of individual lobe values and ranged from 0 (no involvement) to 25 (maximum involvement). Other secondary outcomes included clinical laboratory findings (cytokines, biochemical indicators, etc) and the proportion of patients with clinical improvement. Safety outcomes included adverse events that occurred during treatment and premature discontinuation of treatment. Adverse events were classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0 [Supplementary methods in Supplementary materials, https://links.lww.com/CM9/A929]. A total of 146 COVID-19 patients were recruited, 124 of which were from Tongji Hospital and the rest 22 were from the Central Hospital in Jingzhou. Seventy-three patients were randomly assigned for pirfenidone treatment, and the remaining 73 patients received the standard treatment alone [Supplementary Figure 1, https://links.lww.com/CM9/A647]. The median age of patients was 62.0 years (interquartile range [IQR] 53.5–68.5 years), and 64.38% of patients were males. The median interval time between symptom onset and randomization was 40 days (IQR, 25–50 days). At the time of admission, there were no significant differences between the two groups in terms of demographic characteristics, basic laboratory assays, clinical treatment K-BILD scores, and CT scores [Supplementary Table 1, https://links.lww.com/CM9/A646]. Although the difference of K-BILD scores did not reach a statistical significance after treatment (75.93 ± 10.07 vs. 76.33 ± 9.15, P = 0.911), a trend for the increase from baseline in patients following a 4-week of pirfenidone treatment was noted as compared to that of patients assigned in the standard treatment group (ΔK-BILD, 26.53 ± 11.12 vs. 22.73 ± 8.00; 3.80 [95% confidence interval, CI = −4.87 to 12.47]) [Supplementary Table 2, https://links.lww.com/CM9/A646]. Similarly, there was no significant difference between two groups in terms of CT images (P = 0.745) after a 4-week of treatment, but some score changes including consolidation (0.30 ± 0.65 vs. 1.07 ± 1.17, P = 0.007), GGO (−12.27 ± 5.72 vs. −11.57 ± 4.07; between-group difference = −0.70, 95% CI = −2.97 to 1.57), and reticulation (−0.90 ± 5.26 vs. −0.30 ± 6.98; between-group difference = −0.60, 95% CI = −3.40 to 2.20) were observed, which reflected the improvement of lung inflammation and interstitial changes [Supplementary Table 3, https://links.lww.com/CM9/A646 and Supplementary Figure 2, https://links.lww.com/CM9/A648]. The levels of pulmonary inflammatory cytokines or coagulopathy biomarker from baseline to the 4th week after receiving treatment were significantly decreased in the pirfenidone group as compared to those from the standard care group, such as IL-2R (−299.00, 95% CI = −430.50 to −105.00, P = 0.010), TNF-α (−3.50, 95% CI = −5.00 to −0.10, P = 0.049), and D-Dimer (−4.57, 95% CI = −8.98 to −0.16, P = 0.021) [Supplementary Table 2, https://links.lww.com/CM9/A646]. In addition, the duration of patients in pirfenidone group from randomization to hospital discharge and in intensive care unit was reduced by 2 days (11.21 ± 10.06 vs. 13.21 ± 16.63 days, −2 days, 95% CI = −9.27 to 5.27; 19.00 [IQR 15.00–22.00] vs. 22.00 [IQR 16.50–25.50]; −2 days, 95% CI = −3.50 to 8.50) [Supplementary Table 2, https://links.lww.com/CM9/A646]. No significant difference was noted for other outcomes such as clinical improvement time, duration of oxygen therapy, and time from randomization to death. However, all patients survived in the pirfenidone treatment group, and two patients were declined to death in the standard care group. The proportional distribution of primary endpoint categories at days 1, 7, 14, and 28 in each patient was presented in Supplementary Figure 3, https://links.lww.com/CM9/A649 and Supplementary Table 3, https://links.lww.com/CM9/A646. The percentages of patients with any adverse event or serious adverse event were similar between the patients from both groups. Among patients with adverse events, 11% (8/73) of patients reduced the dose of pirfenidone and 3% (2/73) of patients discontinued. Among those eight patients with pirfenidone reduced-dose, four cases were reduced to 600 mg/day due to gastrointestinal discomfort and the remaining four cases were reduced to 600 mg/day due to rash. The most common adverse event was diarrhea, which was reported in 11 out of 73 (15%) patients from the pirfenidone group. Some patients have elevated alanine aminotransferase and alanine aminotransferase level [Supplementary Figure 3 and Supplementary Table 2, https://links.lww.com/CM9/A646, https://links.lww.com/CM9/A649]. Given that the COVID-19 is a type of infectious disease that could be transmitted through the respiratory tract, lung function test was not included in this study. According to previous studies, patients infected with SARS-CoV-2 are far more likely to form an interstitial change in the lung, while our statistical indicators including K-BILD and CT image ratings reflected improved situation in terms of interstitial changes in pirfenidone treated patients. However, we failed to observe a significant difference between the two groups both for K-BILD and CT scores. Since our observation period only lasted for 4 weeks, our trial did not yield a significantly positive result, and the observation time could be a major factor. It was noted that pirfenidone did not improve fibrosis, but it did not make the disease worse. Nevertheless, pirfenidone did manifest a strong effect on mitigating the cytokine storm, which seems to be responsible for the complications in severe COVID-19 patients. Indeed, comparative analysis revealed that the levels of IL-2R and TNF-α were decreased significantly following pirfenidone administration. Although the anti-inflammatory effect has not been widely appreciated, pirfenidone has been shown to downregulate inflammatory pathways and the compound may have considerable potential to be deployed as a non-steroidal anti-inflammatory agent.[5,6] To our surprise, our study also found that pirfenidone could significantly decrease the level of D-Dimer, which is relevant to the coagulopathy in the blood. There is evidence that COVID-19 renders patients with an increased risk for acute pulmonary embolism, and anticoagulant therapy might be associated with improved outcomes in patients with severe COVID-19.[7] Therefore, treatment of COVID-19 with pirfenidone may have the potential to reduce the incidence of thrombosis complications. The safety and side-effect profile of pirfenidone in patients with severe COVID-19 associated ILD was similar to that observed in patients with IPF.[8] Despite the presence of certain side effects, but they could be easily managed with supporting therapies and temporary dose reductions or discontinuation. No fatal events were reported in our study, confirming the good safety profile of this drug even in fragile patients. Our study also has several limitations. First, our sample size is limited. Second, although we have tried to avoid bias as much as possible during the trial, while this possibility cannot be completely excluded. Third, our trial lacks of dynamic clinical and laboratory data such as immune cell subsets and so on. Finally, our trail only lasted a 4-week of observation time, which could be a factor to confirm the antifibrotic effect of pirfenidone. In addition, glucocorticoids could also be a potential factor influencing the results of the study, even though there was no significant difference in the initial dosage, total dosage, and duration of treatment between the two groups. Although pirfenidone has not been found to significantly improve the interstitial changes in severe COVID-19 patients, the trial, however, confirmed the benefits of pirfenidone therapy in anti-inflammatory responses, and obtained feasible evidence supporting a potential benefit in anti-thrombotic complications. Collectively, our study found that pirfenidone can be considered as a viable drug to treat patients with severe COVID-19, and confirmed that pirfenidone possesses a good tolerability profile without safety alert. Funding This study was supported by grants from the SARS-CoV-2 Pneumonia Emergency Technology Public Relation Project of Tongji Medical College, Huazhong University of Science and Technology (No. 2020kfyXGYJ043), the National Natural Science Foundation of China (No. 81974456); and the SARS-CoV-2 Pneumonia Emergency Technology Public Relation Project (No. 2020FCA009). Conflicts of interest None.

Objective:To explore the effects of ERp57 on fibroblast activation and its function and mechanism in the pathogenesis of pulmonary fibrosis.Methods:Immunohistochemical staining and Western blot were used to detect the expression level of ERp57 in lung tissues of idiopathic pulmonary fibrosis patients and bleomycin-induced pulmonary fibrosis in mice.In vitro, primary lung fibroblasts were cultured and ERp57-siRNA liposomes were transfected into fibroblasts.Western blot was used to detect the effect of siRNA interference with ERp57 expression on the activation of fibroblasts.Results:In the lung tissues of idiopathic pulmonary fibrosis patients and bleomycin-induced pulmonary fibrosis mice, the expression level of ERp57 was significantly up-regulated, and it was mainly expressed in fibroblasts.In vitro, experiments revealed that the expression level of ERp57 increased in a time-dependent manner in human primary fibroblasts after transforming growth factor-β 1 stimulation.In line with those results, knockdown of ERp57 expression can significantly inhibit fibroblast activation. Conclusions:ERp57 is closely related to the pathogenesis of pulmonary fibrosis and suppression of ERp57 expression can significantly inhibit the activation of fibroblasts.

Background Pulmonary mucormycosis caused by Mucorales is a highly lethal invasive fungal infection usually found in immunocompromised patients. Isolated pulmonary mucormycosis in immunocompetent patients is very rare. Here, we present a case of a 32-year-old male who developed pulmonary mucormycosis without any known immunodeficiency. Case presentation The patient presented to our hospital because of cough and chest pain along with blood in the sputum. He was first treated for community-acquired pneumonia until bronchoalveolar lavage fluid culture confirmed the growth of Absidia . His symptoms were relieved with the use of amphotericin B, and he eventually recovered. We also provide a systematic review of relevant literature to summarize the characteristics of pulmonary mucormycosis in immunocompetent patients. Conclusions Pulmonary mucormycosis has variable clinical presentations and is difficult to identify. Due to its high fatality rate, clinicians should make judgements regarding suspected cases correctly and in a timely manner to avoid misdiagnosis and delayed treatment.