Programmed cell death ligand 1 measurement study in granulocyte colony-stimulating factor-producing lung cancer: an observational study.

BACKGROUND: Granulocyte colony-stimulating factor (G-CSF)-producing lung cancer induces severe inflammation and a high white blood cell (WBC) count and is associated with poor prognosis. A recent case of G-CSF-producing lung adenocarcinoma showed high expression of programmed cell death ligand 1 (PD-L1) and was treated with pembrolizumab as first-line therapy, which was extremely effective. We hypothesized that G-CSF-producing lung cancers are associated with high PD-L1 expression. METHODS: This retrospective study included patients diagnosed with lung cancer at Yokohama Municipal Citizen's Hospital (Kanagawa, Japan) between 2009 and 2019. The PD-L1 status of 13 patients with high plasma G-CSF levels (≥40 pg/mL) was assessed by conducting immunohistochemical analysis of tissue samples. RESULTS: Of the total patients, 11 were men and 2 were women, with a median age of 74 years (70-85 years). Four, five, and three patients had adenocarcinoma, squamous cell carcinoma, and others, respectively. The median G-CSF level and WBC count were 85.5 pg/mL (range, 40.8-484 pg/mL) and 15,550/µL (range, 6,190-56,800/µL), respectively. The PD-L1 tumor proportion scores (TPSs) were ≥50%, 1%-49%, and <1% in 9, 1, and 3 patients, respectively. The median overall survival time was 7.3 months. Pembrolizumab was administered in six patients as first-line treatment, with two patients showing partial response, one patient with stable disease, and three patients with progressive disease. All six patients had a PD-L1 TPS of ≥50%. CONCLUSION: G-CSF-producing lung cancers may be associated with increased PD-L1 expression. Although immune checkpoint inhibitors are an important treatment option for G-CSF-producing tumors, their effects are limited.

CD147 Is Essential for the Development of Psoriasis via the Induction of Th17 Cell Differentiation.

Th17 cells play an important role in psoriasis. The differentiation of naïve CD4+ T cells into Th17 cells depends on glycolysis as the energy source. CD147/basigin, an integral transmembrane protein belonging to the immunoglobulin superfamily, regulates glycolysis in association with monocarboxylate transporters (MCTs)-1 and -4 in cancer cells and T cells. We examined whether CD147/basigin is involved in the pathogenesis of psoriasis in humans and psoriasis-model mice. The serum level of CD147 was increased in patients with psoriasis, and the expression of CD147 and MCT-1 was elevated in their dermal CD4+ RORγt+ T cells. In vitro, the potential of naïve CD4+ T cells to differentiate into Th17 cells was abrogated in CD147-/- T cells. Imiquimod (IMQ)-induced psoriatic dermatitis was significantly milder in CD147-/- mice and bone marrow chimeric mice lacking CD147 in the hematopoietic cells of myeloid lineage. These findings demonstrate that CD147 is essential for the development of psoriasis via the induction of Th17 cell differentiation.

High-fat diet exacerbates imiquimod-induced psoriasis-like dermatitis in mice.

Psoriasis, a chronic inflammatory skin disease, is closely related to systemic metabolism. An elevated body mass index (BMI) is a risk factor for psoriasis; inflammasomes are activated by adipose tissue macrophages in obese subjects. We hypothesized that hyperlipidaemia is involved in the pathogenesis of psoriasis and examined the role of a high-fat diet (HFD) in the development of psoriasis in imiquimod (IMQ)-treated mice. The body weight and serum level of cholesterol were significantly higher in mice fed an HFD than in a regular diet (RD). HFD mice had higher psoriasis skin scores, and the number of neutrophils infiltrating into the lesional skin was elevated. IL-17A mRNA expression was significantly increased in the skin of IMQ-treated HFD mice; the expression of IL-22, IL-23 and TNF-α mRNA was not enhanced. Caspase-1 and IL-1ß were activated in the skin of IMQ-treated HFD mice, and their serum level of IL-17A, TNF-α and IL-1ß was significantly upregulated. Our findings strongly suggest that hyperlipidaemia is involved in the development and progression of psoriasis via systemic inflammation and inflammasome activation.

Systemic therapy for psoriasis and the risk of cutaneous infections.

Systemic treatments are important for patients with moderate-to-severe psoriasis; however, they may occasionally cause adverse infectious events. Although the risk of severe infections with psoriatic treatments is well established, little is known about cutaneous infections. Therefore, we studied the frequency of cutaneous infections in patients with psoriasis who underwent biologic treatment. A total of 878 patients (237 females and 641 males) were analyzed in this follow-up survey conducted in 2020 and based on the Western Japan Psoriasis Registry. The observed skin phenotypes were psoriasis vulgaris (83.3%), pustular psoriasis (7.5%), and psoriatic arthritis (28.9%). The most frequently prescribed systemic drug was apremilast (11.3%), followed by ixekizumab (11.0%), risankizumab (10.9%), and secukinumab (10.4%). The incidence of cutaneous bacterial infections was 12 (1.37% of the total patients), with cellulitis being the most common (8/12, 67%). The incidence of viral infections was 11 (1.25%) including the most common, herpes zoster (9/11, 82%); and that of fungal infections was 45 (5.13%) including 33 (73%) and seven (16%) patients with trichophytosis and oral candidiasis, respectively. Multivariate analysis revealed that cutaneous bacterial infections were frequently observed in patients receiving tumor necrosis factor-α (odds raio [OR] 9.917, 95% confidence interval [CI] 2.069-47.572, p = 0.004) and interleukin (IL)-17 (OR 10.798, 95% CI 2.35-49.616, p = 0.002) inhibitor treatments. A history of otitis media and treatment with oral medications (OR 4.50, 95% CI 1.281-15.804, p = 0.019 and OR 3.80, 95% CI 1.141-12.679, p = 0.03 respectively) were associated with a higher ORs for cutaneous viral infections. Furthermore, age and use of IL-17 inhibitors were associated with elevated ORs for fungal infections. In conclusion, our study reveals that systemic therapies may increase the risk of cutaneous viral infections. Therefore, dermatologists should exercise caution in this regard.

Neutrophil-Derived MicroRNA-1290 Promotes Keratinocyte Proliferation in Psoriasis.

The pathological hallmark of psoriasis is the infiltration of neutrophils into the skin. Some neutrophil-derived microRNAs (miRNAs) serve as biomarkers for various diseases, but none have been reported for psoriasis. In this study, we investigated the involvement of miRNAs released from neutrophils in psoriasis pathogenesis. We compared the expression of miRNAs in the sera of patients with psoriasis with that in healthy individuals and found that the expression of 2 miRNAs-miR-223 and miR-1290-was significantly upregulated in the sera of patients with psoriasis. The serum levels of these miRNAs positively correlated with the PASI and CRP levels. We used all-trans retinoic acid to induce the differentiation of human promyelocytic leukemia HL-60 cells into neutrophil-like cells and found that the release of both miRNAs increased during differentiation. Furthermore, the release of miR-1290 was increased by TNF-α in neutrophil-like cells and human neutrophils. Treatment with the miR-1290 precursor promoted the proliferation of human keratinocytes, increased the proportion of S-phase cells, and upregulated the phosphorylation of extracellular signal-regulated kinase 1/2. These results suggest that miR-1290 plays a vital role in regulating neutrophil differentiation and keratinocyte proliferation and could be a serum marker of psoriasis severity.

Multiple lung abscesses and cold agglutinin syndrome following coronavirus disease 2019: a case report.

BACKGROUND: Cold agglutination syndrome is a subtype of autoimmune hemolytic anemia. The condition is referred to as "cold" because the antibodies become active and induce hemolysis at cold temperatures, typically 3-4 °C, which is not always the case in other kinds of autoimmune hemolytic anemia. Whereas primary cold agglutination syndrome may occur in the absence of underlying conditions, secondary cold agglutination syndrome is associated with the presence of underlying infections, including coronavirus disease 2019. CASE PRESENTATION: We report the case of a 69-year-old Japanese woman with periodontitis who was referred to our hospital with complaints of brown-colored urine and chest pain. Her hemoglobin level was 6.1 g/dL. Computed tomography revealed multiple lung abscesses. Her direct antibody test results were positive (2+) for anti-complement direct antiglobulin and negative for immunoglobulin G, and her cold agglutinin titer was elevated at 1:4096. Workup for anemia revealed a positive result for cold agglutination syndrome. The patient had received the fourth dose of coronavirus disease 2019 vaccination. Nasopharyngeal swab test for detecting severe acute respiratory syndrome coronavirus 2 using a real-time reverse-transcription polymerase chain reaction gave a cycle threshold value of 42.3, and the level of virus-specific immunoglobulin G was elevated at 7.71 S/C (normal range -1.4 S/C). CONCLUSION: A decrease in hemoglobin in patients with coronavirus disease 2019 may be associated with secondary cold agglutination syndrome. The patient was hypothesized to have developed multiple lung abscesses with secondary cold agglutination syndrome following coronavirus disease 2019. Thus, following coronavirus disease 2019, patients can develop secondary cold agglutination syndrome, which could worsen owing to associated bloodstream bacterial infections.

The transcription factor Snail expressed in cutaneous squamous cell carcinoma induces epithelial-mesenchymal transition and down-regulates COX-2.

Cutaneous spindle cell squamous cell carcinoma (SCC) is a rare, but highly malignant variant of SCC. The presence of spindle-shaped cells with a sarcomatous appearance, which are derived from squamous cells, suggests that these cells are produced as a result of epithelial-mesenchymal transition (EMT). EMT is a complex process in which epithelial cells lose their polarity and cell-cell contacts, while also acquiring increased motility and invasiveness. Snail regulates EMT by binding to proximal E-boxes in the promoter region of E-cadherin and repressing its transcription. When examining the expression of EMT markers and Snail in spindle cell SCCs, we found that cyclooxygenase-2 (COX-2) expression was down-regulated. Since it has been shown that COX-2 is constitutively overexpressed in a variety of malignancies, including colon, gastric, and lung carcinomas, the down-regulation of COX-2 expression was unexpected. The presence of E-box-like sequences in the promoter region of COX-2 prompted us to perform a more detailed analysis. We introduced a Snail expression vector into keratinocyte-derived cell lines (HaKaT, HSC5, and A431 cells), and isolated stable transfectants. We determined that COX-2 expression was down-regulated in cells expressing Snail. Consistent with these observations, reporter assays revealed that COX-2 promoter activity was repressed upon Snail overexpression. Thus Snail down-regulates COX-2 in these cells.

Japanese black vinegar "Izumi" inhibits the proliferation of human squamous cell carcinoma cells via necroptosis.

Kurozu (Japanese black vinegar), a traditional product made from unpolished rice, contains beneficial organic materials and minerals. Improved manufacturing processes yielded a new vinegar, Izumi, that contains large amounts of these constituents. Because the antioxidative effects of Kurozu are well understood, we examined Izumi for its anticancer activity against the human squamous cell carcinoma (SCC) cell line HSC-5. HSC-5 cells were treated with Izumi or ordinary grain vinegar adjusted to 4.2% acidicity. MTT assay and the trypan blue dye exclusion test showed that Izumi significantly inhibited the proliferation of HSC-5 cells compared to ordinary grain vinegar. Propidium iodide (PI) flow cytometry and annexin V/PI staining revealed that among cells treated or untreated with Izumi or ordinary grain vinegar there was no difference in the number of apoptotic cells. A new form of necrosis, programmed necrosis or necroptosis, has been proposed. It is mediated by receptor-interacting serine-threonine kinase 3 (RIPK3), key signaling molecule, and results in the release of cellular danger-associated molecular patterns (DAMPs). When HSC-5 cells were treated with Izumi, the cellular level of RIPK3 protein and the amount of high-mobility group protein B1, one of the DAMPs, released into culture media were remarkably increased. These findings indicate that Izumi inhibits the proliferation of human SCC cells via programmed necrosis (necroptosis).

A 33-Year-Old Man With Hemoptysis and Renal Dysfunction.

CASE PRESENTATION: A 33-year-old man presented with a 10-day history of fever, dry cough, and dyspnea. He reported small amounts of frank hemoptysis that occurred several times a day for the past 3 days and a reduction in urine volume. There was no joint pain, skin rash, muscle weakness, or bleeding symptoms, except for the hemoptysis. He had a medical history of childhood asthma and untreated hypertension for the past 2 years. He had no history of smoking, recent travel, medication use, or occupational inhalation.

Association of PD-L1 tumor proportion score ≥20% with early resistance to osimertinib in patients with EGFR-mutated NSCLC.

BACKGROUND: The relationship between epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance, including osimertinib, and programmed cell death-ligand 1 (PD-L1) expression status in EGFR-mutated non-small cell lung carcinoma (NSCLC) remains unclear. PATIENTS AND METHODS: We retrospectively analyzed 64 patients with unresectable advanced or metastatic NSCLC carrying EGFR exon 19 deletions (ex19del) or EGFR exon 21 L858R substitutions (L858R) who received osimertinib as the first-line treatment. We compared progression-free survival (PFS) between eligible patients with PD-L1 tumor proportion scores (TPS) ≥20% and PD-L1 TPS <20% using the Kaplan-Meier survival plots with a log-rank test. Multivariate analysis was performed to examine the poor prognostic factors of PFS. RESULTS: The PD-L1 TPS ≥20% group included 22 cases (median [range] age: 70.5 [33-86] years; 10 women [45.5%]; 11 current or ex-smokers [50%]); ECOG performance status (PS) of 0-1/2/3/4 was noted in 16/4/1/1 patients, respectively. The PD-L1 TPS <20% group included 42 patients (median [range] age 73 [43-88] years; 29 women [69%]; 12 current or ex-smokers [28.6%]); ECOG PS of 0-1/2/3/4 was noted in 33/6/3/0 cases, respectively. The median PFS was 9.1 and 28.1 months in the PD-L1 TPS ≥20% and PD-L1 TPS <20% groups, respectively (log-rank p = 0.013). Multivariate analysis revealed that PD-L1 TPS ≥20% was associated with PFS (hazard ratio: 2.35, 95% confidence interval: 1.09-5.08, p = 0.030). CONCLUSION: PD-L1 TPS ≥20% in patients with EGFR-mutated NSCLC may be associated with early resistance to osimertinib.

Survival rates of systemic interventions for psoriasis in the Western Japan Psoriasis Registry: A multicenter retrospective study.

Psoriasis affects approximately 0.3% of the Japanese population. Recently, various effective systemic drugs have become available, and the continuation of a given treatment has become critical because of the chronic nature of psoriasis. Factors affecting drug survival (the time until treatment discontinuation) in psoriasis treatment include efficacy, safety, ease of use, and patient preference. In the present study, the authors retrospectively surveyed a multifacility patient registry to determine the real-world evidence of the survival rate of systemic interventions for psoriasis treatment. Patients with psoriasis who visited 20 facilities in the Western Japan area between January 2019 and May 2020 and gave written consent were registered as study participants, and their medical history of systemic interventions for psoriasis (starting from 2010) was retrospectively collected and analyzed. The drugs investigated were adalimumab, infliximab, ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab, risankizumab, cyclosporine, and apremilast. When drugs were discontinued, the reasons were also recorded. A total of 1003 patients with psoriasis including 268 with psoriatic arthritis (PsA) were enrolled. In biologics, more recently released drugs such as interleukin 17 inhibitors showed a numerically higher survival rate in the overall (post-2010) analysis. However, in the subset of patients who began treatment after 2017, the difference in the survival rate among the drugs was smaller. The reasons for discontinuing drugs varied, but a loss of efficacy against dermatological or joint symptoms were relatively frequently seen with some biologics and cyclosporine. The stratification of drug survival rates based on patient characteristics such as bio-naive or experienced, normal weight or obese, and with or without PsA, revealed that bio-experienced, obese, and PsA groups had poorer survival rates for most drugs. No notable safety issues were identified in this study. Overall, the present study revealed that the biologics show differences in their tendency to develop a loss of efficacy, and the factors that negatively impact the survival rate of biologics include the previous use of biologics, obesity, and PsA.

Clinical characteristics of patients with psoriasis with family history: A multicenter observational study.

Previous studies on family history of psoriasis showed that patients with a family history have an earlier onset of the disease, but such studies in Japan are still limited. To elucidate the characteristics of patients with familial psoriasis, we studied the family history of patients with psoriasis using the West Japan Psoriasis Registry, a multi-institutional registry operated by 26 facilities in the western part of Japan, including university hospitals, community hospitals, and clinics. This study enrolled 1847 patients registered between September 2019 and December 2021, with 199 (10.8%) having a family history of psoriasis. Patients with a family history of psoriasis had significantly earlier onset of the disease than those without a family history. Furthermore, patients with a family history of psoriasis had significantly longer disease duration. Psoriatic arthritis (PsA) was significantly more common in patients with a family history (69/199, 34.7%) than in those without a family history (439/1648, 26.6%) (adjusted P = 0.023). A subanalysis of patients with PsA revealed a significant difference in the patient global assessment (PaGA) score in Fisher's exact test and adjusted test. The numbers of patients with PaGA 0/1 were 29 (43.3%) and 172 (39.9%) in patients with PsA with and without family history of psoriasis, respectively, whereas the numbers of patients with PaGA 3/4 were 13 (19.4%) and 145 (33.6%) in patients with PsA with and without family history of psoriasis, respectively. Other disease severity variables did not show a difference between the two groups. Our findings suggest that genetics play a larger role in the development of PsA than in the development of psoriasis vulgaris. Most cases of PsA occur in patients who already have psoriasis, therefore dermatologists should pay attention to joint symptoms, especially in patients with psoriasis who have a family history of psoriasis.

Cholesterol sulfate induces expression of the skin barrier protein filaggrin in normal human epidermal keratinocytes through induction of RORα.

Cholesterol sulfate is abundant in the human epidermis and is a putative natural ligand for retinoic acid receptor-related orphan receptor alpha (RORα). Although direct binding of cholesterol sulfate is expected to activate RORα, cholesterol sulfate can also induce RORα expression and increase RORα target gene expression. The purpose of this study was to determine whether cholesterol sulfate induces profilaggrin expression, a precursor of the barrier protein filaggrin in the epidermis, through activation of RORα by directly binding to RORα, or through increased RORα expression. Immunohistochemical and polymerase chain reaction (PCR) analyses showed that RORα was expressed in normal human epidermal keratinocytes (NHEKs) and that its expression increased during keratinocyte differentiation in parallel with that of profilaggrin and cholesterol sulfotransferase, which catalyzes the synthesis of cholesterol sulfate. Exogenous cholesterol sulfate significantly increased both RORα and profilaggrin expression in NHEKs, whereas no effect on profilaggrin expression was observed in cells in which RORα was knocked down with small interfering RNA (siRNA). Additionally, a luciferase reporter gene assay revealed that exogenous RORα dose-dependently increased the activity of the profilaggrin gene promoter even in the absence of cholesterol sulfate, and that this response involves activator protein-1. In conclusion, the results of this study indicate that cholesterol sulfate induces filaggrin expression through increased RORα expression. Further studies are required to fully elucidate the mechanisms involved.

Indication for random skin biopsy for the diagnosis of intravascular large B cell lymphoma.

BACKGROUND: The use of random skin biopsy (RSB) to diagnose intravascular large B cell lymphoma (IVLBCL) has increased. OBJECTIVE: To explore the indication for RSB to diagnose IVLBCL. METHODS: We retrospectively evaluated the medical records of 18 Japanese adults who underwent RSB between January 2008 and December 2009. RESULTS: A final diagnosis of IVLBCL was returned in 2 patients based on RSB findings and in 1 based on brain biopsy findings. All 3 patients manifested neurological symptoms, hematocytopenia, elevated levels of LDH and soluble interleukin-2 receptor (sIL-2R), and the absence of lymphadenopathy. Malignant lymphoma other than IVLBCL was diagnosed in 6 patients, and in 5 of 6 patients who underwent nodal or parenchymal biopsy diagnostic findings were made. CONCLUSION: Although RSB is useful for the early diagnosis of IVLBCL, careful selection of patients is necessary. In patients with neurological symptoms, hematocytopenia, elevated LDH and sIL-2R and no nodal involvement, RSB may be useful.

Granulocyte and monocyte adsorptive apheresis for pyoderma gangrenosum.

Pyoderma gangrenosum (PG), a chronic aseptic inflammatory skin disease characterized by skin ulcers with elevated and undermined borders, is resistant to conventional therapies. PG is elicited by activated neutrophils and macrophages and is often associated with systemic diseases such as inflammatory bowel disease, rheumatoid arthritis, aortitis syndrome, and hematopoietic disorders. This single-center study assessed the efficacy and safety of selectively depleting myeloid-lineage leukocytes in patients with PG. Patients with PG, aged 20 or over, received 5 or 10 treatment sessions of granulocyte and monocyte adsorption apheresis (GMA), once or twice a week. Treatment efficacy was assessed based on the rate of skin ulcer reduction, the visual analog scale of pain, and the physician's global assessment of the skin lesions. A complete response (CR) was obtained in eight patients, a nearly complete response (nCR) in three patients, and a partial response (PR) in two patients. In four of the other six, the disease remained stable (SD) and in two we observed disease progression (PD). No severe adverse events were recorded. Our results suggest that GMA is a useful and safe treatment modality for PG.

Clinical characteristics of Japanese pustular psoriasis: A multicenter observational study.

Generalized pustular psoriasis (GPP) is a rare and severe subtype of psoriasis. Because of its rarity, GPP studies with a large sample size have been scarce. We studied the characteristics of GPP and pustular psoriasis using data from the West Japan Psoriasis Registry that had been registered until the end of December 2020. The dataset included 104 patients with pustular psoriasis and 1290 patients with other subtypes of psoriasis. Multivariate analysis revealed a significantly greater number of female patients, a significantly lower mean body mass index, and a significantly lower ratio of habitual drinkers in pustular psoriasis, compared to other subtypes of psoriasis. Of the 104 patients, 102 had GPP, including 88 von Zumbusch, 10 juvenile-onset, and four annular pustular psoriasis. Although the male : female ratio of GPP with psoriasis vulgaris (GPP+PsV) (47/20) was similar to that of psoriasis in Japan, the GPP without PsV (GPP-PsV) group highlighted a female predominance (13/22). The mean age at GPP onset was 45.3 years, and the mean interval from PsV onset to GPP onset was 12.5 years. Four of nine patients with GPP had an IL36RN gene mutation. Infection, medicine, and pregnancy were the precipitating factors for GPP. A family history of psoriasis was present in eight (7.8%) patients with GPP. Twenty-four patients with GPP had psoriatic arthritis. Biologics were used in 76.5% of patients with GPP, followed by etretinate (37.3%), cyclosporine (24.5%), methotrexate (13.7%), apremilast (8.8%), and granulocyte and monocyte adsorption apheresis (6.9%). Etretinate was used in 17 (51.5%) of 33 patients with GPP with less than 10-year history. Thus, etretinate remains a good treatment option for GPP even in the era of biologics. Hypertension was the most commonly identified comorbidity, followed by diabetes. We believe that the characteristics revealed in this study can further contribute to effective GPP management.

Gender disparities in academic dermatology in Japan: Results from the first national survey.

BACKGROUND: A wide gender gap exists in many fields in Japan, including the academic society of dermatology. Women are substantially underrepresented in the highest academic ranks. OBJECTIVE: We aimed to clarify the possible factors contributing to the current gender gap in the field of academic dermatology and to recommend necessary measures to decrease the gender gap. METHODS: We performed a cross-sectional study of faculty members' academic productivity at the dermatology departments of all the educational institutions in Japan in 2019. RESULTS: Women had significantly lower academic productivity than men. A significant gender difference in academic productivity was found in lecturers and assistant professors but not in associate professor and professor positions. This gender difference was still significant after normalizing the productivity for career length. CONCLUSION: Our findings suggest the need to encourage women lecturers and assistant professors to improve their academic achievement to decrease the gender gap in academic dermatology.

Late-onset interstitial nephritis in a patient with drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms.

Drug-induced hypersensitivity syndrome (DIHS), also referred to as drug reaction with eosinophilia and systemic symptoms (DRESS), is a severe hypersensitivity drug reaction affecting the skin and multiple internal organ systems. We report a 47-year-old man with DIHS/DRESS and comorbidities (fulminant type 1 diabetes mellitus, valsartan-induced photosensitivity, vitiligo and acute interstitial nephritis). Although acute interstitial nephritis usually appears in the early phase, his is a rare case of acute interstitial nephritis more than 2 years after the onset of DIHS/DRESS.

Mycobacterium tuberculosis infection in psoriatic patients treated with biologics: Real-world data from 18 Japanese facilities.

Although rare, tuberculosis has been reported with biologic treatment against psoriasis in Japan, a tuberculosis medium-burden country. Mycobacterial infection often develops after a long incubation period and might not have been adequately identified in clinical trials or post-marketing surveillance. To determine the real-world incidence of tuberculosis in psoriatic patients treated with biologics, we conducted a retrospective, multicenter, observational study in 18 facilities in Western Japan. Psoriatic patients who visited a participating facility between 2010 and March 2017 and received biologic reagents were enrolled. Information on sex, age at first biologic treatment, results of interferon-γ release assay (IGRA) for Mycobacterium tuberculosis, treatment history with isoniazid, and onset of active and/or latent tuberculosis was collected. A total of 1117 patients (830 men and 287 women) were enrolled. The mean duration of biologic treatment was 3.54 years. Sixty-five patients (5.8%) showed positive IGRA results at screening. Active tuberculosis developed in two patients after the administration of tumor necrosis factor inhibitors (both involved miliary tuberculosis). Latent tuberculosis was observed in two patients treated with anti-interleukin-12/23p40 antibody. The incidence rate of tuberculosis, including latent tuberculosis, in this survey was 0.36%. Although the incidence rate of tuberculosis was low considering the observation period of biologic treatment, active tuberculosis was found in both the screening-negative group and a screening-positive subject after isoniazid prophylaxis (both miliary tuberculosis), concluding that negative screening or isoniazid treatment does not always assure that an individual has no tuberculosis. Hence, dermatologists still need to pay careful attention to tuberculosis at every patient visit.