Diagnosis of Hypersensitivity Pneumonitis: 2020 Clinical Practice Guideline

Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) characterized by an inhaled inciting antigen that leads to the inflammation of the lung parenchyma and small airway with immunologic reactions. Over the last decades, the most effective therapeutic option for HP has been limited to antigen avoidance. The differential diagnosis of HP from other ILDs is the beginning of treatment as well as diagnosis. However, the presence of several overlapping clinical and radiologic features makes differentiating HP from other ILDs particularly challenging. In 2020, a multidisciplinary committee of experts from the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax suggested a new clinical practice guideline classifying HP into nonfibrotic and fibrotic phenotypes on the basis of chest high-resolution CT (HRCT) findings. Therefore, we introduced a new diagnostic algorithm based on chest HRCT in the clinical practice guideline for the diagnosis of HP.

Diagnosis of Hypersensitivity Pneumonitis: 2020 Clinical Practice Guideline

Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) characterized by an inhaled inciting antigen that leads to the inflammation of the lung parenchyma and small airway with immunologic reactions. Over the last decades, the most effective therapeutic option for HP has been limited to antigen avoidance. The differential diagnosis of HP from other ILDs is the beginning of treatment as well as diagnosis. However, the presence of several overlapping clinical and radiologic features makes differentiating HP from other ILDs particularly challenging. In 2020, a multidisciplinary committee of experts from the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax suggested a new clinical practice guideline classifying HP into nonfibrotic and fibrotic phenotypes on the basis of chest high-resolution CT (HRCT) findings. Therefore, we introduced a new diagnostic algorithm based on chest HRCT in the clinical practice guideline for the diagnosis of HP.

Application of Dual-Energy Spectral Computed Tomography to Thoracic Oncology Imaging

Computed tomography (CT) is an important imaging modality in evaluating thoracic malignancies. The clinical utility of dual-energy spectral computed tomography (DESCT) has recently been realized. DESCT allows for virtual monoenergetic or monochromatic imaging, virtual non-contrast or unenhanced imaging, iodine concentration measurement, and effective atomic number (Zeff map). The application of information gained using this technique in the field of thoracic oncology is important, and therefore many studies have been conducted to explore the use of DESCT in the evaluation and management of thoracic malignancies. Here we summarize and review recent DESCT studies on clinical applications related to thoracic oncology.

A Stepwise Diagnostic Approach to Cystic Lung Diseases for Radiologists

Lung cysts are commonly seen on computed tomography (CT), and cystic lung diseases show a wide disease spectrum. Thus, correct diagnosis of cystic lung diseases is a challenge for radiologists. As the first diagnostic step, cysts should be distinguished from cavities, bullae, pneumatocele, emphysema, honeycombing, and cystic bronchiectasis. Second, cysts can be categorized as single/localized versus multiple/diffuse. Solitary/localized cysts include incidental cysts and congenital cystic diseases. Multiple/diffuse cysts can be further categorized according to the presence or absence of associated radiologic findings. Multiple/diffuse cysts without associated findings include lymphangioleiomyomatosis and Birt-Hogg-Dubé syndrome. Multiple/diffuse cysts may be associated with ground-glass opacity or small nodules. Multiple/diffuse cysts with nodules include Langerhans cell histiocytosis, cystic metastasis, and amyloidosis. Multiple/diffuse cysts with ground-glass opacity include pneumocystis pneumonia, desquamative interstitial pneumonia, and lymphocytic interstitial pneumonia. This stepwise radiologic diagnostic approach can be helpful in reaching a correct diagnosis for various cystic lung diseases.

Accuracy of Model-Based Iterative Reconstruction for CT Volumetry of Part-Solid Nodules and Solid Nodules in Comparison with Filtered Back Projection and Hybrid Iterative Reconstruction at Various Dose Settings: An Anthropomorphic Chest Phantom Study

OBJECTIVE: To investigate the accuracy of model-based iterative reconstruction (MIR) for volume measurement of part-solid nodules (PSNs) and solid nodules (SNs) in comparison with filtered back projection (FBP) or hybrid iterative reconstruction (HIR) at various radiation dose settings. MATERIALS AND METHODS: CT scanning was performed for eight different diameters of PSNs and SNs placed in the phantom at five radiation dose levels (120 kVp/100 mAs, 120 kVp/50 mAs, 120 kVp/20 mAs, 120 kVp/10 mAs, and 80 kVp/10 mAs). Each CT scan was reconstructed using FBP, HIR, or MIR with three different image definitions (body routine level 1 [IMR-R1], body soft tissue level 1 [IMR-ST1], and sharp plus level 1 [IMR-SP1]; Philips Healthcare). The SN and PSN volumes including each solid/ground-glass opacity portion were measured semi-automatically, after which absolute percentage measurement errors (APEs) of the measured volumes were calculated. Image noise was calculated to assess the image quality. RESULTS: Across all nodules and dose settings, the APEs were significantly lower in MIR than in FBP and HIR (all p < 0.01). The APEs of the smallest inner solid portion of the PSNs (3 mm) and SNs (3 mm) were the lowest when MIR (IMR-R1 and IMR-ST1) was used for reconstruction for all radiation dose settings. (IMR-R1 and IMR-ST1 at 120 kVp/100 mAs, 1.06 ± 1.36 and 8.75 ± 3.96, p < 0.001; at 120 kVp/50 mAs, 1.95 ± 1.56 and 5.61 ± 0.85, p = 0.002; at 120 kVp/20 mAs, 2.88 ± 3.68 and 5.75 ± 1.95, p = 0.001; at 120 kVp/10 mAs, 5.57 ± 6.26 and 6.32 ± 2.91, p = 0.091; at 80 kVp/10 mAs, 5.84 ± 1.96 and 6.90 ± 3.31, p = 0.632). Image noise was significantly lower in MIR than in FBP and HIR for all radiation dose settings (120 kVp/100 mAs, 3.22 ± 0.66; 120 kVp/50 mAs, 4.19 ± 1.37; 120 kVp/20 mAs, 5.49 ± 1.16; 120 kVp/10 mAs, 6.88 ± 1.91; 80 kVp/10 mAs, 12.49 ± 6.14; all p < 0.001). CONCLUSION: MIR was the most accurate algorithm for volume measurements of both PSNs and SNs in comparison with FBP and HIR at low-dose as well as standard-dose settings. Specifically, MIR was effective in the volume measurement of the smallest PSNs and SNs.

Pulmonary Artery Intimal Sarcoma versus Pulmonary Artery Thromboembolism: CT and Clinical Findings

OBJECTIVE: To describe CT and clinical findings of pulmonary artery intimal sarcoma (PAIS) compared with those of pulmonary thromboembolism (PTE), to investigate MRI and positron emission tomography (PET)-CT findings of PAIS, and to evaluate the effect of delayed diagnosis of PAIS on survival outcomes. MATERIALS AND METHODS: Twenty-six patients with PAIS were retrospectively identified and matched for sex, with patients with PTE at a ratio of 1:2. CT and clinical findings of the two groups were compared using Student's t test or chi-square test. The effect of delayed diagnosis on survival was investigated using Kaplan-Meier analysis. RESULTS: The most common tumor pattern in PAIS was tumoral impaction. Heterogeneous attenuation, wall eclipse signs, intratumoral vessels, acute interphase angles, single location, presence of lung ischemia, and central location were significantly more common in PAIS than in PTE (all p < 0.01). Levels of D-dimers and brain natriuretic peptide were lower in PAIS than in PTE (p < 0.05). In three patients of PAIS, long inversion time sequence MRI showed intermingled dark signal intensity foci suggestive of intermingled thrombi. All nine patients who had undergone PET-CT displayed hypermetabolism. Diagnosis was delayed in 42.3% of the PAIS patients and those patients had a significantly shorter overall survival than patients whose diagnosis was not delayed (p < 0.05). CONCLUSION: The characteristic CT and clinical findings of PAIS may help achieve early diagnosis of PAIS and make better survival outcomes of patients. MRI and PET-CT can be used as second-line imaging modalities and could help distinguish PAIS from PTE and to plan clinical management.

Comparison of Filtered Back Projection, Hybrid Iterative Reconstruction, Model-Based Iterative Reconstruction, and Virtual Monoenergetic Reconstruction Images at Both Low- and Standard-Dose Settings in Measurement of Emphysema Volume and Airway Wall Thick

OBJECTIVE: To evaluate the accuracy of emphysema volume (EV) and airway measurements (AMs) produced by various iterative reconstruction (IR) algorithms and virtual monoenergetic images (VME) at both low- and standard-dose settings. MATERIALS AND METHODS: Computed tomography (CT) images were obtained on phantom at both low- (30 mAs at 120 kVp) and standard-doses (100 mAs at 120 kVp). Each CT scan was reconstructed using filtered back projection, hybrid IR (iDose4; Philips Healthcare), model-based IR (IMR-R1, IMR-ST1, IMR-SP1; Philips Healthcare), and VME at 70 keV (VME70). The EV of each air column and wall area percentage (WA%) of each airway tube were measured in all algorithms. Absolute percentage measurement errors of EV (APEvol) and AM (APEWA%) were then calculated. RESULTS: Emphysema volume was most accurately measured in IMR-R1 (APEvol in low-dose, 0.053 ± 0.002; APEvol in standard-dose, 0.047 ± 0.003; all p 0.05). VME70 showed a significantly higher APEvol than iDose4, IMR-R1, and IMR-ST1 (all p < 0.004). VME70 also showed a significantly higher APEWA% compared with the other algorithms (all p < 0.001). CONCLUSION: IMR was the most accurate technique for measurement of both EV and airway wall thickness. However, VME70 did not show a significantly better accuracy compared with other algorithms.

Impact of Model-Based Iterative Reconstruction on the Correlation between Computed Tomography Quantification of a Low Lung Attenuation Area and Airway Measurements and Pulmonary Function Test Results in Normal Subjects

OBJECTIVE: To compare correlations between pulmonary function test (PFT) results and different reconstruction algorithms and to suggest the optimal reconstruction protocol for computed tomography (CT) quantification of low lung attenuation areas and airways in healthy individuals. MATERIALS AND METHODS: A total of 259 subjects with normal PFT and chest CT results were included. CT scans were reconstructed using filtered back projection, hybrid-iterative reconstruction, and model-based IR (MIR). For quantitative analysis, the emphysema index (EI) and wall area percentage (WA%) were determined. Subgroup analysis according to smoking history was also performed. RESULTS: The EIs of all the reconstruction algorithms correlated significantly with the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) (all p < 0.001). The EI of MIR showed the strongest correlation with FEV1/FVC (r = −0.437). WA% showed a significant correlation with FEV1 in all the reconstruction algorithms (all p < 0.05) correlated significantly with FEV1/FVC for MIR only (p < 0.001). The WA% of MIR showed the strongest correlations with FEV1 (r = −0.205) and FEV1/FVC (r = −0.250). In subgroup analysis, the EI of MIR had the strongest correlation with PFT in both ever-smoker and never-smoker subgroups, although there was no significant difference in the EI between the reconstruction algorithms. WA% of MIR showed a significantly thinner airway thickness than the other algorithms (49.7 ± 7.6 in ever-smokers and 49.5 ± 7.5 in never-smokers, all p < 0.001), and also showed the strongest correlation with PFT in both ever-smoker and never-smoker subgroups. CONCLUSION: CT quantification of low lung attenuation areas and airways by means of MIR showed the strongest correlation with PFT results among the algorithms used, in normal subjects.

A Radiologic Overview of Aspiration-Induced Lung Disease in Adults

Aspiration is defined as accidental entrance of foreign matter into the lower respiratory tract, and is a common event and can occur in healthy individuals. The type of aspiration-induced lung diseases depends on the quantity and nature of the aspirated material, the chronicity, and the host responses. Aspiration into the airways and lungs can cause a wide spectrum of lung diseases with various manifestations in adults. Diseases with predominantly airway manifestation include foreign body aspiration and diffuse aspiration bronchiolitis. Diseases with predominantly lung parenchymal manifestation include acute diseases such as aspiration pneumonia, aspiration pneumonitis, and near drowning, and chronic diseases such as chronic exogenous lipoid pneumonia and chronic interstitial lung disease. Definitive diagnosis of aspiration-induced lung diseases is challenging to make. Awareness of radiologic findings associated with these diseases is essential for accurate diagnosis and management of these diverse aspiration-induced lung diseases.

Effect of the High-Pitch Mode in Dual-Source Computed Tomography on the Accuracy of Three-Dimensional Volumetry of Solid Pulmonary Nodules: A Phantom Study

OBJECTIVE: To evaluate the influence of high-pitch mode (HPM) in dual-source computed tomography (DSCT) on the accuracy of three-dimensional (3D) volumetry for solid pulmonary nodules. MATERIALS AND METHODS: A lung phantom implanted with 45 solid pulmonary nodules (n = 15 for each of 4-mm, 6-mm, and 8-mm in diameter) was scanned twice, first in conventional pitch mode (CPM) and then in HPM using DSCT. The relative percentage volume errors (RPEs) of 3D volumetry were compared between the HPM and CPM. In addition, the intermode volume variability (IVV) of 3D volumetry was calculated. RESULTS: In the measurement of the 6-mm and 8-mm nodules, there was no significant difference in RPE (p > 0.05, respectively) between the CPM and HPM (IVVs of 1.2 +/- 0.9%, and 1.7 +/- 1.5%, respectively). In the measurement of the 4-mm nodules, the mean RPE in the HPM (35.1 +/- 7.4%) was significantly greater (p < 0.01) than that in the CPM (18.4 +/- 5.3%), with an IVV of 13.1 +/- 6.6%. However, the IVVs were in an acceptable range (< 25%), regardless of nodule size. CONCLUSION: The accuracy of 3D volumetry with HPM for solid pulmonary nodule is comparable to that with CPM. However, the use of HPM may adversely affect the accuracy of 3D volumetry for smaller (< 5 mm in diameter) nodule.

Primary Neuroendocrine Carcinoma of the Breast with Clinical Features of Inflammatory Breast Carcinoma: A Case Report and Literature Review / 한국유방암학회지

Primary neuroendocrine carcinoma of the breast (NECB) is a very rare type of invasive breast carcinoma. Most NECBs appear on breast imaging as solid masses of varied shapes and margins, and have worse clinical outcomes than does invasive ductal carcinoma, not otherwise specified. However, there have been no reports to date regarding NECB with features of inflammatory breast carcinoma. Here, we describe the clinical, radiol-ogic, and pathologic findings of the first reported case of primary NECB presenting as inflammatory breast carcinoma. The patient complained of diffuse right breast enlargement and erythema. Mammography identified severe breast edema and axillary lymphadenopathy. Ultrasound detected an irregular, angular, hypoechoic mass with dermal lymphatic dilatation. On magnetic resonance imaging, the mass had rim enhancement and the entire right breast showed heterogeneous enhancement with malignant kinetic features. Pathology identified the mass as a primary NECB with positive for synaptophysin, CD56, estrogen and progesterone receptors.

Usefulness of Digital Tomosynthesis for the Detection of Airway Obstruction: A Case Report of Bronchial Carcinosarcoma / Journal of the Korean Cancer Association, 대한암학회지

Bronchial carcinosarcoma is a very rare malignant tumor that is composed of carcinomatous and sarcomatous elements. We describe the first case in which digital tomosynthesis was useful for the evaluation of airway obstruction by bronchial carcinosarcoma that was overlooked on initial chest radiography.

Endometrial Stromal Sarcoma Presented as an Incidental Lung Mass with Multiple Pulmonary Nodules / 결핵및호흡기질환

Low-grade endometrial stromal sarcoma (ESS) is an uncommon gynecologic malignancy of mesodermal origin. Pulmonary metastasis of low-grade ESS can occur years and decades after the treatment of the primary disease. Low-grade ESS is frequently mistaken as benign uterine neoplasm like uterine leiomyoma, which can potentially lead to a misdiagnosis. We present a case of a 42-year-old woman with low-grade ESS, that initially presented as an incidental lung mass with multiple pulmonary nodules, seven years after an uterine myomectomy. A 6.9x5.8 cm-sized intrapelvic mass suspected of uterine origin was discovered while searching for potential extrathoracic primary origin. A pelviscopy and simultaneous thoracoscopic lung biopsy were conducted for pathologic diagnosis. Finally, the diagnosis was confirmed as low-grade ESS with lung metastasis based on the histopathologic examination with immunohistochemical stain, which was showed positive for CD10 and hormone receptor markers (estrogen and progesterone receptors) in both pelvic and lung specimens.

Bilateral Locked Facets at Lower Lumbar Spine Without Facet Fracture: A Case Report

Bilateral locked facets at L4-5 without facet fracture is a rarely known disease. We present a case of a 37-year-old male patient diagnosed as traumatic L4-5 bilateral facets dislocation without facet fracture. We carried out open reduction, epidural hematoma removal, posterior interbody fusion. After surgery, we attained rapid improvement of the neurologic deficits and competent stabilization.

The Expression of Cytokine and Chemokine Related with Dendritic Cell and Effector T Cell in Psoriatic Lesions / 대한피부과학회지

BACKGROUND: T cells and dendritic cells (DCs) are more observed in the psoriatic lesion. Inflammatory DCs stimulate T cell differentiation (Th1 or Th17 cells) by producing IL-12 and IL-23 in psoriasis. Th1 expresses CCR5, while CCR6 is expressed by Th17. CCL20, the ligand of CCR6, is expressed mostly in keratinocytes to play an important role in the migration of Th17 cells. Transforming growth factor (TGF)beta inhibits the inflammatory cytokines and induces fibrosis. But, there are still controversies about the role of TGFbeta1 in psoriasis. OBJECTIVE: The purpose of this study is to clarify the pathogenesis of psoriasis by comparing the expression patterns of CD11c/IL-23, CCR5/CCR6, CCR6/CCL20, CD11c, IFN-gamma, and TGFbeta1 among overall lesional assessment (OLA) 1, 3, 5, and the control group. METHODS: We performed CD11c/IL-23, CCR5/CCR6, CCR6/CCL20 double-immunofluorecence and immunohistochemistry of CD11c, IFN-gamma, and TGFbeta1 after classifying the severity of the lesion in 1, 3, 5 with OLA score. RESULTS: As OLA score increased, the infiltration of CD11c+IL-23+ cells, CCR5+ cells, and CCR6+ cells and the expression of CCL20 also showed a significant increase. While IFN-gamma+ cells also increased with the OLA score, TGFbeta1 showed positivity usually in the increased vascular endothelial cells and the number of TGFbeta1+ vascular endothelial cells increased with OLA score. CONCLUSION: From the results, the interaction among the dendritic cell-effector T cell, and cytokine derived from the cells, and chemokine/chemokine receptor was confirmed to be important in pathogenesis of psoriasis. It was also confirmed that TGFbeta1 is not only important at neoangiogenesis, but at inflammatory angiogenesis in psoriasis.

Pityriasis Rotunda Developed during Pregnancy / 대한피부과학회지

Pityriasis rotunda is an uncommon dermatosis characterized by asymptomatic, multiple, widely distributed, round or oval-shaped, hyperpigmented or hypopigmented, fine, scaly patches. They typically involve the abdomen, the trunk and extremities. Histopathologic findings are consistent with ichthyosis vulgaris, such as hyperkeratosis, hypogranulosis or agranulosis, hyperpigmentation of the basal layer in epidermis, and perivascular lymphohistiocytic infiltration in the dermis. Although the etiology of the disease remains unknown, it has been associated with a variety of underlying systemic diseases including infectious diseases, hormonal disorders, malignancies, and chronic disorders. One clinical case has been reported about the occurrence of the disease during pregnancy of a 24-year-old african woman, but there is only one reported case of exacerbation of the disease during pregnancy in Korea. Herein, we report a case of pityriasis rotunda occurring during pregnancy.

Classification of Metastatic versus Non-Metastatic Axillary Nodes in Breast Cancer Patients: Value of Cortex-Hilum Area Ratio with Ultrasound / 한국유방암학회지

PURPOSE: To investigate the significance of the cortex-hilum (CH) area ratio and longitudinal-transverse (LT) axis ratio and the blood flow pattern for diagnosis of metastatic axillary lymph nodes by ultrasound in breast cancer patients. METHODS: From October 2005 to July 2006, we prospectively evaluated axillary nodes with ultrasound in 205 consecutive patients who had category 4B, 4C or 5 breast lesions according to the Breast Imaging Reporting and Data System-Ultrasound (BI-RADS-Ultrasound(R)). Among the 205, there were 24 patients who had pathologic verification of breast cancer and axillary lymph node status. For a total of 80 axillary nodes we measured the areas of the cortex and hilum of lymph nodes and calculated the area ratio. We also measured the length of the longitudinal and transverse axis of the lymph nodes and calculated the length ratio. We evaluated the blood flow pattern on power Doppler imaging and classified each lymph node into a central or peripheral pattern. Diagnostic performance was analyzed according to positive criteria for lymph node metastasis (CH area ratio >2, LT axis ratio <2, peripheral type on power Doppler imaging). RESULTS: The sensitivity of the CH area ratio was superior to that of the LT axis ratio (94.1% vs. 82.3%, p=0.031) and to that of the blood flow pattern (94.1% vs. 29.4%, p=0.009). For specificity, all three evaluating parameters had high values (89.1-95.6%) and no significant differences were found (p=0.121). The CH area ratio had a better positive predictive value than the LT axis ratio (94.1% vs. 80.0%, p=0.030) and power Doppler imaging (94.1% vs. 66.6%, p=0.028). For the negative predictive value, the CH area ratio was superior to the LT axis ratio (95.6% vs. 86.6%, p=0.035) and the blood flow pattern (95.6% vs. 63.0%, p=0.027). CONCLUSION: We recommend the CH area ratio of an axillary lymph node on ultrasound as a quantitative indicator for the classification of lymph nodes. The CH area ratio can improve diagnostic performance when compared with the LT axis ratio or blood flow pattern.

Cryoglobulinemia Associated with Gastric Diffuse Large B Cell Lymphoma / 대한피부과학회지

Cryoglobulinemia, first described by Wintrobe and Buell in 1933, is characterized by the presence of serum immunoglobulins that precipitate below 37degrees C and that dissolve on rewarming. Although the actual mechanism of cryoprecipitation and the etiology of cryoglobulinemia remains obscure, it is frequently associated with other systemic diseases, such as hepatitis C virus (HCV) infection, multiple myeloma, Sjogren's syndrome, B cell lymphoma, and systemic lupus erythematosus. No cases of cryoglobulinemia associated with B cell lymphoma have ever been published in the Korean medical literature, and few such cases have been reported in other countries. Herein, we report on a rare and interesting case of cryoglobulinemia developed in a patient with gastric diffuse large B cell lymphoma.

CD20 Positive T Cell Lymphoma Involvement of Skin

CD20 positive T cell lymphoma is a rare condition that is associated with the coexpressions of CD20 and T cell markers, such as, CD3, CD5, or UCHL-1. Positivity for CD20 in this tumor represents an aberrant immunophenotype, but the presence of monoclonal T cell receptor (TCR) gene rearrangements and negativity for immunoglobulin heavy chain gene rearrangement indicate that this tumor is a T cell lymphoma. The majority of cases of CD20 positive T cell lymphoma have been reported as immature peripheral T cell lymphoma not otherwise specified. However, we believe that this disease is likely to be re-listed as a new disease entity after its pathogenesis has been elucidated and more cases have been evaluated. Here, we present a case of peripheral T cell lymphoma coexpressing CD20 and T cell markers with a demonstrable TCR gene rearrangement, in a patient who had been misdiagnosed as having B cell type lymphoma 4 years previously. We hypothesize that in this case initially circulating normal CD20+ T cell subsets underwent neoplastic transformation and CD20 positive T cell lymphoma subsequently developed in the lymph node, and then recurred in the skin due to systemic disease or metastasized from the nodal disease.

Malassezia folliculitis Resembling Erythema Annulare Centrifugum / 대한피부과학회지

Malassezia yeasts are lipophilic fungi that are regarded as normal flora of the skin. They are associated with a number of diseases affecting human skin, such as pityriasis versicolor, Malassezia folliculitis, and seborrheic dermatitis, and less commonly with other dermatologic disorders, such as confluent and reticulated papillomatosis and transient acantholytic dermatosis. Clinically, Malassezia folliculitis shows erythematous papules, sometimes pustules. Here, mutiple erythematous papules and pustules over the trunk and upper arms developed in a 37-year-old man. The skin lesions became enlarged and confluent, resulting in the formation of an annular configuration. They spread gradually to form a large plaque with central hyperpigmentation, with the edge of the lesions showing multiple papules and pustules. Microspores were found in potassium hydroxide preparations of these lesions, and large-sized circular, cream colored, raised, smooth, and dentate colonies were found in culture media. Histologically, sectioning showed mild acanthosis of the epidermis and perivascularinflammation in the superficial dermis. PAS-stained sections showed spheric to oval yeast organisms in the follicularepithelium. In PCR analysis, Malassezia sympodialis was identified. The patient was treated with oral itraconazle, resulting in complete clearing of the lesions. Here, we report an interesting case of Malassezia follicultis that showed clinical configuration of erythema annulare centrifugum.