Inhibition of a Microbiota-Derived Peptide Ameliorates Established Acute Lung Injury.

Acute lung injury (ALI) is a clinical syndrome characterized by a diffuse lung inflammation that commonly evolves into acute respiratory distress syndrome and respiratory failure. The lung microbiota is involved in the pathogenesis of ALI. Corisin, a proapoptotic peptide derived from the lung microbiota, plays a role in ALI and acute exacerbation of pulmonary fibrosis. Preventive therapeutic intervention with a monoclonal anticorisin antibody inhibits ALI in mice. However, whether inhibition of corisin with the antibody ameliorates established ALI is unknown. Here, the therapeutic effectiveness of the anticorisin antibody in already established ALI in mice was assessed. Lipopolysaccharide was used to induce ALI in mice. After causing ALI, the mice were treated with a neutralizing anticorisin antibody. Mice treated with the antibody showed significant improvement in lung radiological and histopathologic findings, decreased lung infiltration of inflammatory cells, reduced markers of lung tissue damage, and inflammatory cytokines in bronchoalveolar lavage fluid compared with untreated mice. In addition, the mice treated with anticorisin antibody showed significantly increased expression of antiapoptotic proteins with decreased caspase-3 activation in the lungs compared with control mice treated with an irrelevant antibody. In conclusion, these observations suggest that the inhibition of corisin is a novel and promising approach for treating established ALI.

Amelioration of Pulmonary Fibrosis by Matrix Metalloproteinase-2 Overexpression.

Idiopathic pulmonary fibrosis is a progressive and fatal disease with a poor prognosis. Matrix metalloproteinase-2 is involved in the pathogenesis of organ fibrosis. The role of matrix metalloproteinase-2 in lung fibrosis is unclear. This study evaluated whether overexpression of matrix metalloproteinase-2 affects the development of pulmonary fibrosis. Lung fibrosis was induced by bleomycin in wild-type mice and transgenic mice overexpressing human matrix metalloproteinase-2. Mice expressing human matrix metalloproteinase-2 showed significantly decreased infiltration of inflammatory cells and inflammatory and fibrotic cytokines in the lungs compared to wild-type mice after induction of lung injury and fibrosis with bleomycin. The computed tomography score, Ashcroft score of fibrosis, and lung collagen deposition were significantly reduced in human matrix metalloproteinase transgenic mice compared to wild-type mice. The expression of anti-apoptotic genes was significantly increased, while caspase-3 activity was significantly reduced in the lungs of matrix metalloproteinase-2 transgenic mice compared to wild-type mice. Active matrix metalloproteinase-2 significantly decreased bleomycin-induced apoptosis in alveolar epithelial cells. Matrix metalloproteinase-2 appears to protect against pulmonary fibrosis by inhibiting apoptosis of lung epithelial cells.

Transforming Growth Factorß1 Overexpression Is Associated with Insulin Resistance and Rapidly Progressive Kidney Fibrosis under Diabetic Conditions.

Diabetes mellitus is a global health problem. Diabetic nephropathy is a common complication of diabetes mellitus and the leading cause of end-stage renal disease. The clinical course, response to therapy, and prognosis of nephropathy are worse in diabetic than in non-diabetic patients. The role of transforming growth factorß1 in kidney fibrosis is undebatable. This study assessed whether the overexpression of transforming growth factorß1 is associated with insulin resistance and the rapid progression of transforming growth factorß1-mediated nephropathy under diabetic conditions. Diabetes mellitus was induced with streptozotocin in wild-type mice and transgenic mice with the kidney-specific overexpression of human transforming growth factorß1. Mice treated with saline were the controls. Glucose tolerance and kidney fibrosis were evaluated. The blood glucose levels, the values of the homeostasis model assessment for insulin resistance, and the area of kidney fibrosis were significantly increased, and the renal function was significantly impaired in the diabetic transforming growth factorß1 transgenic mice compared to the non-diabetic transgenic mice, diabetic wild-type mice, and non-diabetic mice. Transforming growth factorß1 impaired the regulatory effect of insulin on glucose in the hepatocyte and skeletal muscle cell lines. This study shows that transforming growth factorß1 overexpression is associated with insulin resistance and rapidly progressive kidney fibrosis under diabetic conditions in mice.

Thrombomodulin ameliorates transforming growth factor-ß1-mediated chronic kidney disease via the G-protein coupled receptor 15/Akt signal pathway.

Kidney fibrosis is the common consequence of chronic kidney diseases that inexorably progresses to end-stage kidney disease with organ failure treatable only with replacement therapy. Since transforming growth factor-ß1 is the main player in the pathogenesis of kidney fibrosis, we posed the hypothesis that recombinant thrombomodulin can ameliorate transforming growth factor-ß1-mediated progressive kidney fibrosis and failure. To interrogate our hypothesis, we generated a novel glomerulus-specific human transforming growth factor-ß1 transgenic mouse to evaluate the therapeutic effect of recombinant thrombomodulin. This transgenic mouse developed progressive glomerular sclerosis and tubulointerstitial fibrosis with kidney failure. Therapy with recombinant thrombomodulin for four weeks significantly inhibited kidney fibrosis and improved organ function compared to untreated transgenic mice. Treatment with recombinant thrombomodulin significantly inhibited apoptosis and mesenchymal differentiation of podocytes by interacting with the G-protein coupled receptor 15 to activate the Akt signaling pathway and to upregulate the expression of anti-apoptotic proteins including survivin. Thus, our study strongly suggests the potential therapeutic efficacy of recombinant thrombomodulin for the treatment of chronic kidney disease and subsequent organ failure.

Protein S protects against allergic bronchial asthma by modulating Th1/Th2 balance.

BACKGROUND: Bronchial asthma is a chronic disease characterized by inflammation, obstruction, and hyperresponsiveness of the airways. There is currently no curative therapy for asthma. Type 2 helper T cell response plays a critical role in the pathogenesis of the disease. Protein S is a glycoprotein endowed with anticoagulant, anti-inflammatory, and anti-apoptotic properties. Whether protein S can suppress bronchial asthma and be useful for its therapy is unknown. METHODS: To address this question here we compared the development of allergen-associated bronchial asthma between wild type and protein S-overexpressing transgenic mice. Mice were sensitized and challenged with ovalbumin. We also evaluated the circulating levels of total and active protein S in patients with bronchial asthma and healthy controls. RESULTS: The circulating level of total protein S and of its active form was significantly decreased in patients with bronchial asthma compared to controls. Allergic protein S transgenic mice showed a significant reduction of airway hyperresponsiveness, lung tissue inflammatory cell infiltration, lung levels of Th2 cytokines and IgE compared to their wild-type counterparts. Administration of exogenous human protein S also decreased airway hyperresponsiveness and Th2-mediated lung inflammation in allergic wild-type mice compared with their untreated mouse counterparts. Human protein S significantly shifted the Th1/Th2 balance to Th1 and promoted the secretion of Th1 cytokines (IL-12, tumor necrosis factor-α) from dendritic cells. CONCLUSIONS: These observations suggest the strong protective activity of protein S against the development of allergic bronchial asthma implicating its potential usefulness for the disease treatment.

Protein S Exacerbates Chronic Liver Injury and Fibrosis.

Protein S is a vitamin K-dependent glycoprotein produced mainly in the liver with anticoagulant, anti-inflammatory, immune-modulatory, and antiapoptotic properties. Protein S exacerbates acute liver injury by prolonging the survival of liver immune cells. However, the effect of protein S on chronic liver injury and fibrosis is unknown. Here, we investigated whether human protein S can affect chronic liver injury and fibrosis. Liver injury/fibrosis was induced by carbon tetrachloride injection in mice overexpressing human protein S and in wild-type mice. Human protein S transgenic mice receiving carbon tetrachloride showed significantly higher circulating levels of liver transaminases, increased liver expression of inflammatory cytokines, significantly more extended liver fibrosis, and areas with DNA breakage after chronic injury compared with wild-type mice. Wild-type mice infused with exogenous human protein S exhibited exacerbated liver injury and increased number of hepatic stellate cells compared with untreated mice. Human protein S inhibited apoptosis and increased Akt pathway activation in hepatic stellate cells. The antiapoptotic activity of protein S may play a role in chronic liver injury and subsequent liver fibrosis.

Factors leading to failure to diagnose pulmonary malignant tumors using endobronchial ultrasound with guide sheath within the target lesion.

BACKGROUND: The diagnostic yield of peripheral pulmonary lesions has significantly increased with the use of radial endobronchial ultrasound with guide sheath within the lesion. Here, we retrospectively evaluated factors leading to misdiagnosis of pulmonary malignant tumors using endobronchial ultrasound with the guide sheath within the lesion. METHODS: We assessed the final histopathological diagnosis of biopsy samples taken from 130 patients with lung malignant tumors that underwent endobronchial ultrasound with guide sheath within the lesion. RESULTS: Among 130 patients, 8 (6%) showed no definite malignant findings in biopsy samples but the presence of malignant cells (primary lung cancer 7, diffuse large B cell lymphoma 1) was subsequently confirmed by histopathological study of specimens taken by computed tomography-guided needle biopsy or surgery. Of the eight cases with diagnostic failure, the size of the biopsy sample was insufficient in five due to technical difficulties during the diagnostic procedure, and the diagnosis of malignant tumor was difficult in five cases because of extensive scarring tissue or central necrosis. CONCLUSIONS: The results of this study showed that technical difficulties and/or pathological heterogeneity of the tumor might lead to failure to diagnose lung malignant tumor in cases using endobronchial ultrasound with guide sheath within the lesion.

Protein S is Protective in Acute Lung Injury by Inhibiting Cell Apoptosis.

Acute lung injury is a fatal disease characterized by inflammatory cell infiltration, alveolar-capillary barrier disruption, protein-rich edema, and impairment of gas exchange. Protein S is a vitamin K-dependent glycoprotein that exerts anticoagulant, immunomodulatory, anti-inflammatory, anti-apoptotic, and neuroprotective effects. The aim of this study was to evaluate whether human protein S inhibits cell apoptosis in acute lung injury. Acute lung injury in human protein S transgenic and wild-type mice was induced by intratracheal instillation of lipopolysaccharide. The effect of human protein S on apoptosis of lung tissue cells was evaluated by Western blotting. Inflammatory cell infiltration, alveolar wall thickening, myeloperoxidase activity, and the expression of inflammatory cytokines were reduced in human protein S transgenic mice compared to the wild-type mice after lipopolysaccharide instillation. Apoptotic cells and caspase-3 activity were reduced while phosphorylation of extracellular signal-regulated kinase was enhanced in the lung tissue from human protein S transgenic mice compared to wild-type mice after lipopolysaccharide instillation. The results of this study suggest that human protein S is protective in lipopolysaccharide-induced acute lung injury by inhibiting apoptosis of lung cells.

Mice overexpressing latent matrix metalloproteinase-2 develop lung emphysema after short-term exposure to cigarette smoke extract.

Chronic obstructive pulmonary disease is the major growing cause of mortality and morbidity worldwide, and it is going to become the third most common cause of death by 2020. Chronic obstructive pulmonary disease is pathologically characterized by lung emphysema and small airway inflammation. Animal models are very important to get insights into the disease pathogenesis but current models of chronic obstructive pulmonary disease take a long time to develop. The need of a new model is compelling. In the present study we focus on the role of matrix metalloproteinases in the pathogenesis of chronic obstructive pulmonary disease and hypothesized that lung overexpression of latent matrix metalloproteinases-2 would allow the development of emphysema after short-term exposure to cigarette smoke extract inhalation. Human latent matrix metalloproteinases-2 transgenic mouse expressing high level of the protein in the lungs and wild type mouse were exposed to aerosolized cigarette smoke extract for two weeks. Transgenic mice showed significant lung emphysematous changes, increased infiltration of inflammatory cells and enhanced lung concentrations of inflammatory cytokines in the lungs compared to their wild type counterparts after inhalation of cigarette smoke extract. This novel mouse model will be a very useful tool for evaluating the mechanistic pathways and for development of novel therapies in cigarette smoke-associated lung emphysema.

Inhibition of Cell Apoptosis and Amelioration of Pulmonary Fibrosis by Thrombomodulin.

Pulmonary fibrosis is the terminal stage of a group of idiopathic interstitial pneumonias, of which idiopathic pulmonary fibrosis is the most frequent and fatal form. Recent studies have shown that recombinant human thrombomodulin (rhTM) improves exacerbation and clinical outcome of idiopathic pulmonary fibrosis, but the mechanism remains unknown. This study evaluated the mechanistic pathways of the inhibitory activity of rhTM in pulmonary fibrosis. Transgenic mice overexpressing human transforming growth factor-ß1 that develop spontaneously pulmonary fibrosis, and wild-type mice treated with bleomycin were used as models of lung fibrosis. rhTM was administered to mice by i.p. injection or by the intranasal route. Therapy with rhTM significantly decreased the concentration of high mobility group box1, interferon-γ, and fibrinolytic markers, the expression of growth factors including transforming growth factor-ß1, and the degree of lung fibrosis. rhTM significantly suppressed apoptosis of lung epithelial cells in in vivo and in vitro experiments. The results of the present study demonstrated that rhTM can inhibit bleomycin-induced pulmonary fibrosis and transforming growth factor-ß1-driven exacerbation and progression of pulmonary fibrosis, and that apart from its well-recognized anticoagulant and anti-inflammatory properties, rhTM can also suppress apoptosis of lung epithelial cells.

Renal Injury during Long-Term Crizotinib Therapy.

Crizotinib is highly effective against anaplastic lymphoma kinase-positive and c-ros oncogen1-positive non-small cell lung cancer. Renal dysfunction is associated with crizotinib therapy but the mechanism is unknown. Here, we report a case of anaplastic lymphoma kinase positive non-small cell lung cancer showing multiple cysts and dysfunction of the kidneys during crizotinib administration. We also present results demonstrating that long-term crizotinib treatment induces fibrosis and dysfunction of the kidneys by activating the tumor necrosis factor-α/nuclear factor-κB signaling pathway. In conclusion, this study shows the renal detrimental effects of crizotinib, suggesting the need of careful monitoring of renal function during crizotinib therapy.

ß2 adrenergic agonist suppresses eosinophil-induced epithelial-to-mesenchymal transition of bronchial epithelial cells.

BACKGROUND: Epithelial-mesenchymal transition is currently recognized as an important mechanism for the increased number of myofibroblasts in cancer and fibrotic diseases. We have already reported that epithelial-mesenchymal transition is involved in airway remodeling induced by eosinophils. Procaterol is a selective and full ß2 adrenergic agonist that is used as a rescue of asthmatic attack inhaler form and orally as a controller. In this study, we evaluated whether procaterol can suppress epithelial-mesenchymal transition of airway epithelial cells induced by eosinophils. METHODS: Epithelial-mesenchymal transition was assessed using a co-culture system of human bronchial epithelial cells and primary human eosinophils or an eosinophilic leukemia cell line. RESULTS: Procaterol significantly inhibited co-culture associated morphological changes of bronchial epithelial cells, decreased the expression of vimentin, and increased the expression of E-cadherin compared to control. Butoxamine, a specific ß2-adrenergic antagonist, significantly blocked changes induced by procaterol. In addition, procaterol inhibited the expression of adhesion molecules induced during the interaction between eosinophils and bronchial epithelial cells, suggesting the involvement of adhesion molecules in the process of epithelial-mesenchymal transition. Forskolin, a cyclic adenosine monophosphate-promoting agent, exhibits similar inhibitory activity of procaterol. CONCLUSIONS: Overall, these observations support the beneficial effect of procaterol on airway remodeling frequently associated with chronic obstructive pulmonary diseases.

A case of rapidly progressive insulin-dependent diabetes mellitus without islet autoantibodies developed over two years after the first dose of nivolumab.

The case was an 80-year-old Japanese man. He was diagnosed with right renal cell carcinoma when he was 74. After laparoscopic radical nephrectomy, the patient received interferon, sorafenib, axitinib, and nivolumab therapy. The patient developed rapid progressive insulin-dependent diabetes mellitus (DM) after 46 courses of nivolumab monotherapy (772 days from the first nivolumab treatment). Glutamic acid decarboxylase antibody, islet cell cytoplasmic antibody, islet cell antigen-2 antibody, insulin antibody, and zinc transporter 8 antibody were all negative. Human leukocyte antigen (HLA) typing showed DRB1*09:01, DRB1 *13:02, DQB1*03:03, and DQB1 *06:04. Multiple daily insulin injections were started. However, controlling his blood glucose by standard multiple daily insulin injection treatments was difficult. The patient survived more than two years after the onset of immune checkpoint inhibitor-associated DM (ICI-DM). This is a valuable report of late-onset ICI-DM with a detailed patient background and clinical course over two years after the first dose of nivolumab.

Role of microbiota-derived corisin in coagulation activation during SARS-CoV-2 infection.

BACKGROUND: Coagulopathy is a major cause of morbidity and mortality in COVID-19 patients. Hypercoagulability in COVID-19 results in deep vein thrombosis, thromboembolic complications, and diffuse intravascular coagulation. Microbiome dysbiosis influences the clinical course of COVID-19. However, the role of dysbiosis in COVID-19-associated coagulopathy is not fully understood. OBJECTIVES: The present study tested the hypothesis that the microbiota-derived proapoptotic corisin is involved in the coagulation system activation during SARS-CoV-2 infection. METHODS: This cross-sectional study included 47 consecutive patients who consulted for symptoms of COVID-19. A mouse acute lung injury model was used to recapitulate the clinical findings. A549 alveolar epithelial, THP-1, and human umbilical vein endothelial cells were used to evaluate procoagulant and anticoagulant activity of corisin. RESULTS: COVID-19 patients showed significantly high circulating levels of corisin, thrombin-antithrombin complex, D-dimer, tumor necrosis factor-α, and monocyte-chemoattractant protein-1 with reduced levels of free protein S compared with healthy subjects. The levels of thrombin-antithrombin complex, D-dimer, and corisin were significantly correlated. A monoclonal anticorisin-neutralizing antibody significantly inhibited the inflammatory response and coagulation system activation in a SARS-CoV-2 spike protein-associated acute lung injury mouse model, and the levels of corisin and thrombin-antithrombin complex were significantly correlated. In an in vitro experiment, corisin increased the tissue factor activity and decreased the anticoagulant activity of thrombomodulin in epithelial, endothelial, and monocytic cells. CONCLUSION: The microbiota-derived corisin is significantly increased and correlated with activation of the coagulation system during SARS-CoV-2 infection, and corisin may directly increase the procoagulant activity in epithelial, endothelial, and monocytic cells.

Bilateral Nephrectomy for Resistant Hypertension and Secondary Aldosteronism in a Hemodialysis Patient: A Case Report.

A 42-year-old Japanese woman with end-stage renal failure due to hypertension presented with a systolic blood pressure of 160-200 mmHg despite treatment with 4 different antihypertensive agents. The plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were elevated. Adrenal vein sampling suggested bilateral excessive aldosterone secretion, whereas adrenocortical scintigraphy showed right-dominant accumulation. Open bilateral nephrectomy and right adrenalectomy improved the systolic blood pressure, PAC, and PRA. A pathological examination revealed zona glomerulosa hyperplasia but not microaldosteronoma. This report shows that bilateral nephrectomy, not unilateral adrenalectomy, is a potentially effective treatment option for resistant hypertension with an elevated renin-angiotensin-aldosterone system in hemodialysis patients.

Adrenocorticotropic hormone-secreting pancreatic neuroendocrine carcinoma with multiple organ infections and widespread thrombosis: A case report.

BACKGROUND: Ectopic adrenocorticotropic hormone (ACTH)-secreting neuroendocrine tumors are rare diseases. Patients with ACTH-secreting pancreatic neuroendocrine carcinomas have a poor prognosis. Infections and coagulopathies have been reported as the cause of death. However, detailed clinical descriptions of the morbid complications of ACTH-secreting neuroendocrine carcinomas have not been reported. CASE SUMMARY: A 78-year-old Japanese woman consulted a medical center due to systemic edema and epigastric discomfort. Laboratory analysis revealed hypercortisolemia with increased ACTH secretion without diurnal variation in serum cortisol level. An enhanced computed tomography (CT) scan revealed a 3-cm tumor in the pancreatic head. The cytological material from endoscopic ultrasound-guided fine-needle aspiration was compatible with ACTH-secreting pancreatic neuroendocrine carcinoma. The Ki-67 index was 40%. She was transferred to Mie University Hospital for surgical treatment. The patient was diagnosed with urinary tract infection, cytomegalovirus hepatitis, esophageal candidiasis, pulmonary infiltrates suspicious for Pneumocystis carinii pneumonia, peripheral deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. The multiple organ infections and thromboses responded well to antimicrobial and anticoagulant therapy. Radioisotope studies disclosed a pancreatic tumor and a metastatic lesion in the liver, whereas somatostatin receptor scintigraphy showed negative findings, suggesting the primary and metastatic tumors were poorly differentiated. A CT scan before admission showed no metastatic liver lesion, suggesting that the pancreatic tumor was rapidly progressing. Instead of surgery, antitumor chemotherapy was indicated. The patient was transferred to another hospital to initiate chemotherapy. However, she died four months later due to the rapidly progressive tumor. CONCLUSION: ACTH-secreting pancreatic neuroendocrine neoplasm is a rare disease with a very poor prognosis. The clinical course and acute complications of the tumor remain unreported. Here we report the clinical course of a rapidly progressive case of ACTH-secreting pancreatic neuroendocrine tumor that developed infectious complications due to many types of pathogens in multiple organs, widespread thromboses, pulmonary embolism, and disseminated intravascular coagulation.

The Fairy Chemical Imidazole-4-carboxamide Inhibits the Expression of Axl, PD-L1, and PD-L2 and Improves Response to Cisplatin in Melanoma.

The leading cause of death worldwide is cancer. Many reports have proved the beneficial effect of mushrooms in cancer. However, the precise mechanism is not completely clear. In the present study, we focused on the medicinal properties of biomolecules released by fairy ring-forming mushrooms. Fairy chemicals generally stimulate or inhibit the growth of surrounding vegetation. In the present study, we evaluated whether fairy chemicals (2-azahypoxanthine, 2-aza-8-oxohypoxanthine, and imidazole-4-carboxamide) exert anticancer activity by decreasing the expression of Axl and immune checkpoint molecules in melanoma cells. We used B16F10 melanoma cell lines and a melanoma xenograft model in the experiments. Treatment of melanoma xenograft with cisplatin combined with imidazole-4-carboxamide significantly decreased the tumor volume compared to untreated mice or mice treated cisplatin alone. In addition, mice treated with cisplatin and imidazole-4-carboxamide showed increased peritumoral infiltration of T cells compared to mice treated with cisplatin alone. In vitro studies showed that all fairy chemicals, including imidazole-4-carboxamide, inhibit the expression of immune checkpoint molecules and Axl compared to controls. Imidazole-4-carboxamide also significantly blocks the cisplatin-induced upregulation of PD-L1. These observations point to the fairy chemical imidazole-4-carboxamide as a promising coadjuvant therapy with cisplatin in patients with cancer.

Inhibition of lung microbiota-derived proapoptotic peptides ameliorates acute exacerbation of pulmonary fibrosis.

Idiopathic pulmonary fibrosis is an incurable disease of unknown etiology. Acute exacerbation of idiopathic pulmonary fibrosis is associated with high mortality. Excessive apoptosis of lung epithelial cells occurs in pulmonary fibrosis acute exacerbation. We recently identified corisin, a proapoptotic peptide that triggers acute exacerbation of pulmonary fibrosis. Here, we provide insights into the mechanism underlying the processing and release of corisin. Furthermore, we demonstrate that an anticorisin monoclonal antibody ameliorates lung fibrosis by significantly inhibiting acute exacerbation in the human transforming growth factorß1 model and acute lung injury in the bleomycin model. By investigating the impact of the anticorisin monoclonal antibody in a general model of acute lung injury, we further unravel the potential of corisin to impact such diseases. These results underscore the role of corisin in the pathogenesis of acute exacerbation of pulmonary fibrosis and acute lung injury and provide a novel approach to treating this incurable disease.

Case Report: A Difficult-to-Diagnose Case of Hyperinsulinemic Hypoglycemia Surgically Treated After Developing Acute Pancreatitis.

The patient is a 28-year-old Japanese man diagnosed with severe congenital hyperinsulinemic-hypoglycemia six months after birth. Clinical records revealed no imaging evidence of pancreatic tumor at the time of diagnosis. Subsequently, he had developmental disorders and epilepsy caused by recurrent hypoglycemic attacks. The patient's hypoglycemia improved with oral diazoxide. However, he developed necrotizing acute pancreatitis at 28 years of age, thought to be due to diazoxide. Discontinuation of diazoxide caused persistent hypoglycemia, requiring continuous glucose supplementation by tube feeding and total parenteral nutrition. A selective arterial secretagogue injection test revealed diffuse pancreatic hypersecretion of insulin. He underwent subtotal distal (72%) pancreatectomy and splenectomy. There was no intraoperative visible pancreatic tumor. His hypoglycemia improved after the surgical procedure. The histopathological study revealed a high density of islets of Langerhans in the pancreatic body and tail. There were large islets of Langerhans and multiple neuroendocrine cell nests in the whole pancreas. Nests of neuroendocrine cells were also detected in lymph nodes. The pathological diagnosis was grade 1 neuroendocrine tumor (microinsulinomas) with lymph node metastases. This patient is a difficult-to-diagnose case of hyperinsulinemic hypoglycemia surgically treated after developing acute pancreatitis. We believe this is a unique case of microinsulinomas with lymph metastases diagnosed and treated as congenital hyperinsulinemic hypoglycemia for almost 28 years.