Elevated blood bicarbonate levels and long-term adverse outcomes in patients with chronic heart failure.

AIMS: The bicarbonate (HCO3 -) buffer system is crucial for maintaining acid-base homeostasis and blood pH. Recent studies showed that elevated serum HCO3 - levels serve as an indicator of the beneficial effects of acetazolamide in improving decongestion in acute heart failure. In this study, we sought to clarify the clinical relevance and prognostic impact of HCO3 - in chronic heart failure (CHF). METHODS: This cohort study enrolled 694 hospitalized patients with CHF (mean age 68.6 ± 14.6, 62% male) who underwent arterial blood sampling and exhibited neutral pH ranging from 7.35 to 7.45. We characterized the patients based on HCO3 - levels and followed them to register cardiac events. RESULTS: Among the patients, 17.3% (120 patients) had HCO3 - levels exceeding 26 mmol/L. Patients presenting HCO3 - > 26 mmol/L were more likely to use loop diuretics and had higher serum sodium and lower potassium levels, but left ventricular ejection fraction did not differ compared with those with HCO3 - between 22 and 26 (379 patients) or those with HCO3 - < 22 mmol/L (195 patients). During a median follow-up period of 1950 days, Kaplan-Meier analysis revealed that patients with HCO3 - > 26 mmol/L had the lowest event-free survival rate from either cardiac deaths or heart failure-related rehospitalization (P < 0.01 and 0.03, respectively). In the multivariable Cox model, the presence of HCO3 - > 26 mmol/L independently predicted increased risks of each cardiac event with a hazard ratio of 2.31 and 1.69 (P < 0.01 and 0.02, respectively), while HCO3 - < 22 mmol/L was not associated with these events (hazard ratios, 0.99 and 1.19; P = 0.98 and 0.43, respectively). CONCLUSIONS: Elevated blood HCO3 - levels may signify enhanced proximal nephron activation and loop diuretic resistance, leading to long-term adverse outcomes in patients with CHF, even within a normal pH range.

FOUR-WEEK ORAL ADMINISTRATION OF BALOXAVIR MARBOXIL AS AN ANTI-INFLUENZA VIRUS DRUG SHOWS NO TOXICITY IN CHICKENS.

High pathogenicity avian influenza is an acute zoonotic disease with high mortality in birds caused by a high pathogenicity avian influenza virus (HPAIV). Recently, HPAIV has rapidly spread worldwide and has killed many wild birds, including endangered species. Baloxavir marboxil (BXM), an anti-influenza agent used for humans, was reported to reduce mortality and virus secretion from HPAIV-infected chickens (Gallus domesticus, order Galliformes) at a dosage of ≥2.5 mg/kg when administered simultaneously with viral challenge. Application of this treatment to endangered birds requires further information on potential avian-specific toxicity caused by repeated exposure to BXM over the long term. To obtain information of potential avian-specific toxicity, a 4-wk oral repeated-dose study of BXM was conducted in chickens (n = 6 or 7 per group), which are commonly used as laboratory avian species. The study was conducted in reference to the human pharmaceutical guidelines for nonclinical repeated-dose drug toxicity studies to evaluate systemic toxicity and exposure. No adverse changes were observed in any organs examined, and dose proportional increases in systemic exposure to active pharmaceutical ingredients were noted from 12.5 to 62.5 mg/kg per day. BXM showed no toxicity to chickens at doses of up to 62.5 mg/kg per day, at which systemic exposure was approximately 71 times higher than systemic exposure at 2.5 mg/kg, the reported efficacious dosage amount, in HPAIV-infected chickens. These results also suggest that BXM could be considered safe for treating HPAIV-infected endangered birds due to its high safety margin compared with the efficacy dose. The data in this study could contribute to the preservation of endangered birds by using BXM as a means of protecting biodiversity.

Are trunk muscle sizes different between acute lumbar spondylolysis and nonspecific low back pain?

INTRODUCTION: Morphological differences in the trunk muscles between adolescent athletes with lumbar spondylolysis (LS) and nonspecific low back pain (NSLBP) have not been fully elucidated. This study aimed to investigate the differences in physiological cross-sectional areas (CSA) of the trunk muscles between athletes with acute LS and those with acute NSLBP. METHODS: Magnetic resonance images of 48 patients aged 13-14 years diagnosed with acute LS or NSLBP were retrospectively evaluated. The CSA of the paraspinal, psoas major, and rectus abdominis muscles at the L4-5 intervertebral disc level were measured. RESULTS: CSA of the left and right paraspinal muscles in the acute LS group were significantly larger than those in the acute NSLBP group (left: mean difference, 276.0 mm2; 95% confidence interval [CI], 68.5-483.6 mm2; P = 0.01; right: mean difference, 228.8 mm2; 95% CI, 7.6-450.1 mm2; P = 0.04). The ratio between the left paraspinal muscles and left psoas major in the acute LS group was significantly larger than that in the acute NSLBP group (mean difference, 0.2; 95% CI, 0.0-0.4; P = 0.03). CONCLUSIONS: Trunk muscle size may differ between adolescent athletes with acute LS and those with NSLBP. Future research involving healthy controls is required to better understand the morphological characteristics of these injuries.

The potential of the transformer-based survival analysis model, SurvTrace, for predicting recurrent cardiovascular events and stratifying high-risk patients with ischemic heart disease.

INTRODUCTION: Ischemic heart disease is a leading cause of death worldwide, and its importance is increasing with the aging population. The aim of this study was to evaluate the accuracy of SurvTrace, a survival analysis model using the Transformer-a state-of-the-art deep learning method-for predicting recurrent cardiovascular events and stratifying high-risk patients. The model's performance was compared to that of a conventional scoring system utilizing real-world data from cardiovascular patients. METHODS: This study consecutively enrolled patients who underwent percutaneous coronary intervention (PCI) at the Department of Cardiovascular Medicine, University of Tokyo Hospital, between 2005 and 2019. Each patient's initial PCI at our hospital was designated as the index procedure, and a composite of major adverse cardiovascular events (MACE) was monitored for up to two years post-index event. Data regarding patient background, clinical presentation, medical history, medications, and perioperative complications were collected to predict MACE. The performance of two models-a conventional scoring system proposed by Wilson et al. and the Transformer-based model SurvTrace-was evaluated using Harrell's c-index, Kaplan-Meier curves, and log-rank tests. RESULTS: A total of 3938 cases were included in the study, with 394 used as the test dataset and the remaining 3544 used for model training. SurvTrace exhibited a mean c-index of 0.72 (95% confidence intervals (CI): 0.69-0.76), which indicated higher prognostic accuracy compared with the conventional scoring system's 0.64 (95% CI: 0.64-0.64). Moreover, SurvTrace demonstrated superior risk stratification ability, effectively distinguishing between the high-risk group and other risk categories in terms of event occurrence. In contrast, the conventional system only showed a significant difference between the low-risk and high-risk groups. CONCLUSION: This study based on real-world cardiovascular patient data underscores the potential of the Transformer-based survival analysis model, SurvTrace, for predicting recurrent cardiovascular events and stratifying high-risk patients.

First molecular characterization of Burkholderia mallei strains isolated from horses in Mongolia.

Glanders, a highly contagious and often fatal disease affecting equids, is caused by Burkholderia mallei. Although sporadic cases of equine glanders have recently been documented in Mongolia, genome sequencing and molecular studies of the bacteria within this region are lacking. This study provided the first molecular characterization of B. mallei isolated from four native Mongolian horses from two different provinces in 2019 and 2022 by applying whole-genome sequencing with two SNP types (previously developed genotyping with 15 SNP markers that provide global coverage of the B. mallei population and the core genome coding SNP typing developed in this study). The Mongolian isolates were located within the L3B1 cluster, which was previously associated with the V-120 strain from Russia. Within the L3B1 cluster shared by neighboring countries, they were in a unique subbranch. In this study, specific SNP markers unique to the Mongolian strains were identified to track these strains using a high-resolution melting analysis (HRMA). This study revealed the unique phylogenetic background of Mongolian strains isolated from the eastern part of Mongolia. HRMA specific to the Mongolian subbranch may contribute to the molecular epidemiological monitoring of glanders in Mongolia and surrounding countries.

Neutrophil Extracellular Traps in Myocardial Tissue Drive Cardiac Dysfunction and Adverse Outcomes in Patients With Heart Failure With Dilated Cardiomyopathy.

BACKGROUND: The immune systems and chronic inflammation are implicated in the pathogenesis of dilated cardiomyopathy (DCM) and heart failure. However, the significance of neutrophil extracellular traps (NETs) in heart failure remains to be elucidated. METHODS: We enrolled consecutive 62 patients with heart failure with idiopathic DCM who underwent endomyocardial biopsy. Biopsy specimens were subjected to fluorescent immunostaining to detect NETs, and clinical and outcome data were collected. Ex vivo and in vivo experiments were conducted. RESULTS: The numbers of NETs per myocardial tissue area and the proportion of NETs per neutrophil were significantly higher in patients with DCM compared with non-DCM control subjects without heart failure, and the numbers of NETs were negatively correlated with left ventricular ejection fraction. Patients with DCM with NETs (n=32) showed lower left ventricular ejection fraction and higher BNP (B-type natriuretic peptide) than those without NETs (n=30). In a multivariable Cox proportional hazard model, the presence of NETs was independently associated with an increased risk of adverse cardiac events in patients with DCM. To understand specific underlying mechanisms, extracellular flux analysis in ex vivo revealed that NETs-containing conditioned medium from wild-type neutrophils or purified NET components led to impaired mitochondrial oxygen consumption of cardiomyocytes, while these effects were abolished when PAD4 (peptidyl arginine deiminase 4) in neutrophils was genetically ablated. In a murine model of pressure overload, NETs in myocardial tissue were predominantly detected in the acute phase and persisted throughout the ongoing stress. Four weeks after transverse aortic constriction, left ventricular ejection fraction was reduced in wild-type mice, whereas PAD4-deficient mice displayed preserved left ventricular ejection fraction without inducing NET formation. CONCLUSIONS: NETs in myocardial tissue contribute to cardiac dysfunction and adverse outcomes in patients with heart failure with DCM, potentially through mitochondrial dysfunction of cardiomyocytes.

Controlled crystallisation of porous crystals of luminescent platinum(II) complexes by electronic tuning of ancillary ligands.

Porous molecular crystals (PMCs) have gained significant importance as next-generation functional porous materials. However, the selective crystallisation of the PMC phase remains a challenge. Herein, we have systematically controlled the stability of the luminescent PMC phase prepared using the luminescent Pt(II) complex [Pt(pbim)(N^O)] (pbim = 2-phenylbenzimidazolate, N^O = N-heteroaryl carboxylate) with Pt⋯Pt electronic interactions. The PMC phase formation varied significantly among the complexes depending on the heteroaryl group of the ancillary N^O ligand; the oxazolyl-bearing complex did not form a PMC phase, whereas the pyrazyl- and 5-fluoropyridyl-bearing complexes spontaneously formed a porous structure. This difference was rationalised by the π-stacking capability of the heteroaryl group of the ancillary ligand. Furthermore, owing to the presence of the one-dimensional Pt⋯Pt chains in this PMC phase, the photophysical properties of PMCs resulting from the Pt⋯Pt interactions were also significantly changed by the ancillary ligands.

Anthracycline-based hepatic arterial infusion chemotherapy achieved 17 months of disease regression in a patient with breast cancer liver metastases resistant to multiple systemic chemotherapies.

Hepatic arterial infusion chemotherapy (HAIC) for liver metastases (LMs) from breast cancer is not a standard of care, but its effectiveness in patients with extensive LMs who cannot tolerate systemic therapy has been reported. Herein, we report a case of breast cancer LMs that were controlled by anthracycline-based HAIC. A 46-year-old woman with estrogen receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer who had multiple LMs and bone metastases underwent seven lines of systemic therapy (paclitaxel/bevacizumab for 38 months; letrozole, nivolumab/fulvestrant, eribulin, gemcitabine/vinorelbine, high-dose toremifene/abemaciclib, and capecitabine for 21 months in total). However, owing to its adverse effects and the continued progression of the LMs, systemic therapy was switched to HAIC (40 mg/body epirubicin on day 1, 4 mg/body mitomycin C on days 1 and 15, and 500 mg/body 5-fluorouracil on days 1, 8, and 15; 28-day courses). In response to HAIC, the LMs remarkably regressed and were controlled for 17 months without severe adverse effects. HAIC was stopped when multiple brain metastases arose, and the patient died 2 months later. This case suggests that HAIC is a reasonable option for patients with extensive LMs, even in the late stage of treatment. HAIC recipients should be carefully selected through multidisciplinary discussions as the survival benefits of HAIC over systemic treatment remain unclear. Our findings identify a potential window for the use of traditional chemotherapeutic agents such as anthracyclines. Novel strategies to improve drug delivery are warranted in the future.

A case of rapidly progressing sarcomatous intrahepatic cholangiocarcinoma with suddenly appearing lymph node metastasis.

BACKGROUND: The sarcomatous variant of carcinoma is relatively rare in intrahepatic cholangiocarcinoma (ICC). Sarcomatous ICC (SICC) is associated with a poorer prognosis compared with ICC. SICC is rarely diagnosed before surgery due to non-descriptive findings; it progresses rapidly, resulting in miserable prognosis. Here, we report a case of rapidly progressing SICC that showed a clinically significant tumor growth rate. CASE PRESENTATION: A 77-year-old woman who had undergone ileocecal resection for cecal cancer 5 years previously was found to have elevated levels of the tumor marker carbohydrate antigen 19-9. Although an abdominal computed tomography (CT) scan did not detect any liver mass lesions until 3 months before this serum examination, the subsequent CT scan revealed a hypodensity 20 mm mass lesion in the right anterior section. Contrast-enhanced CT and magnetic resonance imaging revealed peripheral enhancement in the arterial-to-equilibrium phase. Fluorodeoxyglucose positron emission tomography revealed uptake in the lesion. None of the imaging modalities showed lymph node swelling or distant metastases. She underwent hepatectomy under the diagnosis of ICC or an atypical metastasis from previous cecal cancer. Although preoperative images showed no suspicious lymph node metastasis 3 weeks prior, the hilar lymph node swelled 3 cm and contained adenocarcinoma. Consequently, the patient underwent right anterior sectionectomy and lymph node dissection of the hepatoduodenal ligament. Histopathological examination revealed that the liver tumor was a poorly differentiated adenocarcinoma with sarcomatous pattern. While the patient received adjuvant gemcitabine and S-1 therapy, lymph node metastasis appeared in the mediastinum 13 months after the surgery. She received gemcitabine + cisplatin + S-1 therapy but died 20 months after surgery. CONCLUSION: SICC and lymph node metastasis clinically appeared within 3 months and 3 weeks, respectively. Suspected ICC that rapidly progresses should be considered SICC and treated with early resection. SICC is often missed in clinical diagnosis and has a poor prognosis, even after curative resection. While an alternative strategy involving preoperative biopsy and neoadjuvant therapy may be beneficial, it should be approached with discretion due to the potential risks of tumor progression and peritoneal dissemination.

Predictive Value of Aortic Valve Calcium Volume Measured by Computed Tomography for Paravalvular Leakage After Transcatheter Aortic Valve Implantation.

Paravalvular leakage (PVL) is a complication of transcatheter aortic valve implantation (TAVI) for aortic stenosis, leading to an adverse prognosis. We investigated whether aortic valve calcium volume (Ca-Vol) measured by preoperative cardiac computed tomography had a predictive value for PVL after TAVI using a third-generation self-expandable valve.We retrospectively analyzed 59 consecutive patients who underwent TAVI using a third-generation self-expandable valve. We measured Ca-Vol in the aortic valve and each cusp (non-coronary cusp [NCC], right-coronary cusp [RCC], and left-coronary cusp [LCC]). We divided the patients into 2 groups: a PVL group (32.2%) and a non-PVL group (67.8%). Total Ca-Vol was significantly higher in the PVL group than in the non-PVL group (P < 0.001). Ca-Vol in each cusp was also significantly higher in the PVL group ([NCC] P < 0.001, [RCC] P = 0.001, [LCC] P < 0.001). Univariate logistic regression analysis for PVL indicated that the total and per-cusp Ca-Vols were predictors for PVL (total, odds ratio [OR] 4.0, P < 0.001; NCC, OR 12.5, P = 0.002; RCC, OR 16.0, P = 0.008; LCC, OR 44.5, P < 0.001).Receiver operating characteristic curve analysis of Ca-Vol for predicting PVL revealed the optimal cut-off values of Ca-Vol were 2.4 cm3 for the total, 0.74 cm3 for NCC, 0.73 cm3 for RCC, and 0.56 cm3 for LCC (area under the curve, 0.85, 0.79, 0.76, and 0.83, respectively).Preoperative total, NCC, RCC, and LCC calcium volumes were significant predictors for PVL after TAVI using third-generation self-expandable valves.

Multimodality Risk Assessment of Patients with Ischemic Heart Disease Using Deep Learning Models Applied to Electrocardiograms and Chest X-rays.

Comprehensive management approaches for patients with ischemic heart disease (IHD) are important aids for prognostication and treatment planning. While single-modality deep neural networks (DNNs) have shown promising performance for detecting cardiac abnormalities, the potential benefits of using DNNs for multimodality risk assessment in patients with IHD have not been reported. The purpose of this study was to investigate the effectiveness of multimodality risk assessment in patients with IHD using a DNN that utilizes 12-lead electrocardiograms (ECGs) and chest X-rays (CXRs), with the prediction of major adverse cardiovascular events (MACEs) being of particular concern.DNN models were applied to detection of left ventricular systolic dysfunction (LVSD) on ECGs and identification of cardiomegaly findings on CXRs. A total of 2107 patients who underwent elective percutaneous coronary intervention were categorized into 4 groups according to the models' outputs: Dual-modality high-risk (n = 105), ECG high-risk (n = 181), CXR high-risk (n = 392), and No-risk (n = 1,429).A total of 342 MACEs were observed. The incidence of a MACE was the highest in the Dual-modality high-risk group (P < 0.001). Multivariate Cox hazards analysis for predicting MACE revealed that the Dual-modality high-risk group had a significantly higher risk of MACE than the No-risk group (hazard ratio (HR): 2.370, P < 0.001), the ECG high-risk group (HR: 1.906, P = 0.010), and the CXR high-risk group (HR: 1.624, P = 0.018), after controlling for confounding factors.The results suggest the usefulness of multimodality risk assessment using DNN models applied to 12-lead ECG and CXR data from patients with IHD.

Calcium-Phosphorus Product Is Associated with Adverse Prognosis in Hospitalized Patients with Heart Failure and Chronic Kidney Disease.

It has been reported that high levels of calcium-phosphorus (Ca-P) product are an indicator of coronary calcification and mortality risk in patients undergoing chronic hemodialysis. In the present study, we aimed to evaluate the significance of Ca-P product to predict the prognosis of patients with heart failure (HF) and chronic kidney disease (CKD). We conducted a prospective observational study of 793 patients with decompensated HF and CKD, and measured the value of Ca-P product. The cut-off value was obtained from the survival classification and regression tree (CART) analysis to predict post-discharge all-cause mortality and/or worsening HF, and the patients were divided into 2 groups: a high group (Ca-P product > 28, n = 594) and a low group (Ca-P product ≤ 28, n = 199). We compared the patient baseline characteristics and post-discharge prognosis between the 2 groups. The age as well as the prevalence of male sex, ischemic etiology, and anemia were significantly higher in the low group than in the high group. In contrast, there was no difference in echocardiographic parameters between the 2 groups. In the Kaplan-Meier analysis (mean follow-up 1089 days), all-cause mortality and/or worsening HF event rates were higher in the low group than in the high group (log-rank P = 0.001). In the multivariable Cox proportional hazard analysis, lower Ca-P product was found to be an independent predictor of all-cause mortality and/or worsening HF (hazard ratio 0.981, P = 0.031). Lower Ca-P product predicts adverse prognosis in patients with HF and CKD.

Geriatric Nutritional Risk Index predicts bleeding event in patients with heart failure.

AIMS: We aimed to elucidate the association between malnutrition and the occurrence of bleeding events in patients with heart failure. METHODS AND RESULTS: We evaluated the nutritional status of patients with heart failure [n = 2044, median (inter-quartile range) age 69.0 (59.0-78.0) years, 1209 (59.1%) males] using the Geriatric Nutritional Risk Index (GNRI). The primary endpoint was a composite of bleeding events such as haemorrhagic stroke or gastrointestinal bleeding. According to the survival classification and regression tree analysis, the accurate cut-off point of GNRI for predicting the primary endpoint was 106.2. We divided the patients into two groups based on GNRI levels: high GNRI group (GNRI ≥ 106.2, n = 606, 29.6%) and low GNRI group (GNRI < 106.2, n = 1438, 70.4%). We compared the patients' characteristics and prognosis between the two groups. The low GNRI group was older [72.0 (63.0-79.0) vs. 63.0 (53.0-73.0) years, P < 0.001] and had a lower prevalence of male sex (56.9% vs. 64.5%, P = 0.001). There were no differences in the use of antiplatelet agents and anticoagulants between the two groups. Levels of B-type natriuretic peptide were higher [321.1 (123.3-667.4) vs. 111.6 (42.6-235.4) pg/mL, P < 0.001] and levels of haemoglobin were lower [12.4 (10.8-13.7) vs. 14.2 (12.9-15.4) g/dL, P < 0.001] in the low GNRI group. The Kaplan-Meier analysis demonstrated that bleeding event rates were higher in the low GNRI group (log-rank P < 0.001). The multivariable Cox proportional hazard analysis revealed that low GNRI (hazard ratio 1.952, 95% confidence interval 1.002-3.805, P = 0.049) was associated with bleeding events. CONCLUSIONS: Heart failure patients with poor nutritional status, determined by GNRI under 106.2, experienced high bleeding event rates. Comprehensive management is required to avoid bleeding event in those populations.

Perioperative immunosuppressive therapy and coronary ostial angioplasty for unstable angina with Takayasu arteritis.

A young female patient with Takayasu arteritis presented with unstable angina due to bilateral coronary artery involvement. Steroid pulse therapy and subsequent prednisolone administration were started, but early coronary artery bypass grafting was required because of the multiple angina attacks at rest, with a prednisolone dose of 22.5 mg (0.45 mg/kg/day). Since the left internal thoracic artery which was grafted to the left anterior descending artery resulted in graft failure a few days after the surgery, the immunosuppressive therapy was intensified with the addition of tocilizumab and methotrexate. After controlling the disease activity, coronary ostial angioplasty using external iliac artery grafts was successfully performed, with a prednisolone dose of 15 mg (0.3 mg/kg/day). Ten months after the operation, the patient has been free from chest pain. The present case demonstrated the importance of adequate preoperative immunosuppressive therapy, even when early surgical intervention is required. Learning objective: There are no established treatment regimens for immunosuppressive management in cases of Takayasu arteritis (TAK) requiring immediate surgical intervention. Even when early surgery is required, it is important to reduce disease activity with appropriate preoperative immunosuppressive therapy using steroids in addition to biological agents, such as tocilizumab. Coronary ostial angioplasty is the effective surgical revascularization technique for TAK with coronary artery involvement.

Experimental evaluation of pathogenicity and acquired immunity of Eimeria species, E. uekii and E. raichoi, infecting Japanese rock ptarmigans in a subspecies of the birds.

Japanese rock ptarmigans (Lagopus muta japonica) are birds that inhabit only alpine regions of central Honshu Island, Japan, known as the Japanese Alps. The number of these birds has recently declined, and in situ and ex situ national conservation programs for Japanese rock ptarmigans have been initiated. The infections of Eimeria spp. as protozoan parasites of the phylum Apicomplexa, E. uekii and E. raichoi, were frequently reported in the birds. However, the virulence of these Eimeria parasites has not been determined. Here, we analyzed the pathogenicity of these Eimeria parasites using experimental infections of a subspecies model of Japanese rock ptarmigans, Svalbard rock ptarmigans (Lagopus mutus hyperboreus), and evaluated acquired protective immunity against challenge in birds tolerant of low-dose inoculation with Eimeria parasites. Following inoculation with two Eimeria parasites derived from Japanese rock ptarmigans (dose range of 4 × 104 to 4 × 102 for E. uekii and 1.7 × 104 to 4 × 101 for E. raichoi), oocysts were detected at 6-8 days post-inoculation (PI), and the maximum number of oocysts per gram of feces was observed 7-10 days PI and then gradually decreased. The mortality rate and reduction in weight gain of chicks increased following high-dose inoculation of oocysts with abnormal feces (soft and diarrhea). Developmental zoites were detected histopathologically in epithelial tissues and sometimes the lamina propria from the duodenum to the colon. Chicks that survived low-dose inoculation did not show clear clinical symptoms after challenge inoculation. Our results suggest that the pathological characteristics of Eimeria parasites infecting Japanese rock ptarmigans include abnormal feces and reduction in weight gain, resulting in mortality in cases of heavy infection due to high-dose inoculation. These findings provide helpful data for Japanese rock ptarmigan conservation efforts.