RESUMEN
Congenital protein C (PC) deficiency is one type of hereditary thrombosis. Patients with hereditary thrombosis are at high risk for thrombosis in the perioperative period, but a standard management strategy has not been established. Here we report a case of perioperative management of a fracture in a child with homozygous congenital PC deficiency. The patient was a 3-year-old boy who was diagnosed with congenital PC deficiency at birth. He sustained a traumatic supracondylar fracture of the right humerus and underwent emergency surgery. To prepare for open surgery for fixation of the fracture, warfarin was discontinued, and an activated PC (APC) concentrate was used in combination with vitamin K antagonism. However, warfarin was administered during the scheduled nail extraction because the operation was minimally invasive. No thrombotic or bleeding complications occurred in either operation. In emergency surgery in patients with congenital PC deficiency, the combination of vitamin K and APC concentrate is considered a maintenance option for PC deficiency. Postoperative PT-INR control was difficult in our patient due to the administration of vitamin K and withdrawal of warfarin, and this issue must be addressed in the future. Further case experience is desirable to standardize perioperative management.
Asunto(s)
Fracturas Óseas , Deficiencia de Proteína C , Trombosis , Preescolar , Humanos , Recién Nacido , Masculino , Anticoagulantes , Fracturas Óseas/complicaciones , Deficiencia de Proteína C/complicaciones , Trombosis/complicaciones , Vitamina K , Warfarina/uso terapéuticoRESUMEN
Hereditary protein C deficiency is a chromosomal genetic disease caused by mutations in the protein C gene,which can lead to venous thrombosis and is mostly related to mutations in exons 4-9 and intron 8.Fatal pulmonary embolism caused by mutations in the protein C gene is rare,and the treatment faces great challenges.This article reports a case of fatal pulmonary embolism caused by a frameshift mutation in exon 8 of the protein C gene and summarizes the treatment experience of combining extracorporeal membrane oxygenation (for respiratory and circulatory support) with interventional thrombectomy,providing a basis for the diagnosis and treatment of this disease.
Asunto(s)
Oxigenación por Membrana Extracorpórea , Deficiencia de Proteína C , Embolia Pulmonar , Trombectomía , Humanos , Masculino , Oxigenación por Membrana Extracorpórea/métodos , Mutación del Sistema de Lectura , Deficiencia de Proteína C/complicaciones , Embolia Pulmonar/terapia , Embolia Pulmonar/etiología , Trombectomía/métodos , Persona de Mediana EdadRESUMEN
Objectives: Protein C (PC) is an anticoagulant that is encoded by the PROC gene. Validation for the function of PC was carried out in mouse models. Methods: In this study, autosomal recessive PC deficiency (PCD) was selected as the target, and the specific mutation site was chromosome 2 2q13-q14, PROC c.1198G>A (p.Gly400Ser) which targets G399S (GGT to AGC) in mouse models. To investigate the role of hereditary PC in mice models, we used CRISPR/Cas9 gene editing technology to create a mouse model with a genetic PCD mutation. Results: The two F0 generation positive mice produced using the CRISPR/Cas9 gene editing technique were chimeras, and the mice in F1 and F2 generations were heterozygous. There was no phenotype of spontaneous bleeding or thrombosis in the heterozygous mice, but some of them were blind. Blood routine results showed no significant difference between the heterozygous mice and wild-type mice (P > 0.05). Prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT) were prolonged in the heterozygous mice, while the level of fibrinogen content (FIB) decreased, suggesting secondary consumptive coagulation disease. The protein C activity of heterozygous mice was significantly lower than that of wild-type mice (P < 0.001), but there was no significant difference in protein C antigen levels (P > 0.05). H&E staining showed steatosis and hydrodegeneration in the liver of heterozygous mice. Necrosis and exfoliated epithelial cells could be observed in renal tubule lumen, forming cell or granular tubules. Hemosiderin deposition was found in the spleen along with splenic hemorrhage. Immunohistochemistry demonstrated significant fibrin deposition in the liver, spleen, and kidney of heterozygous mice. Conclusion: In this study, heterozygotes of the mouse model with a PC mutation were obtained. The function of PC was then validated in a mouse model through genotype, phenotype, and PC function analysis.
Asunto(s)
Modelos Animales de Enfermedad , Proteína C , Animales , Proteína C/metabolismo , Proteína C/genética , Ratones , Deficiencia de Proteína C/genética , Mutación , Masculino , Femenino , Coagulación Sanguínea/genética , Heterocigoto , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , Tiempo de Tromboplastina ParcialRESUMEN
Proteins C and S are vitamin K-dependent anticoagulative factors that also exert a significant influence on bone quality. Clinical studies have linked the deficiency of proteins C and S to lower bone mineral density and the onset of femoral head osteonecrosis in children. Rare foundational studies analyzing this topic have demonstrated that activated protein C, upon binding to the endothelial protein C receptor expressed on the surface of osteoblasts, promotes osteoblast proliferation. It is also established that proteins C and S play crucial roles in proper collagen synthesis and in maintaining the number of osteoclasts and blood vessels. However, the association between protein C and/or S deficiency and the gradual onset of osteoporosis remains largely uninvestigated. Calculations based on data from peer-reviewed journals suggest that approximately one in every 10 individuals may develop osteoporosis due to congenital protein C or S deficiency. Moreover, when secondary causes of protein C and S deficiency are also considered, the proportion likely further increases. In this paper, we discuss the pathophysiological background of the potential relationship between protein C and S deficiency and the genesis of osteoporosis.
Asunto(s)
Osteoporosis , Deficiencia de Proteína C , Deficiencia de Proteína S , Humanos , Osteoporosis/etiología , Deficiencia de Proteína C/complicaciones , Deficiencia de Proteína S/complicaciones , Proteína C/metabolismo , Densidad Ósea , Animales , Proteína S/metabolismoRESUMEN
OBJECTIVE: To analyze the clinical features and gene mutations in four families with hereditary protein C (PC) deficiency and explore their association with vascular thromboembolism. METHODS: The clinical data of four patients with PC deficiency were retrospectively analyzed. Venous blood samples were collected from the four affected patients and their family members, and relevant coagulation indexes and thrombin production and inhibition tests were performed. PCR was used to amplify and directly sequence the PROC gene of the probands. Software analysis was conducted to assess the conservativeness and pathogenicity of the mutated loci. Protein models were constructed to analyze the spatial structure before and after the mutation. RESULTS: Thrombin generation and inhibition assays demonstrated impaired anticoagulation in all four probands. Proband 1 and 4 presented clinically with pulmonary embolism and lower extremity deep vein thrombosis (DVT), Proband 2 with cerebral infarction, and Proband 3 with DVT. Genetic analysis revealed the presence of the following mutations: c.541T > G heterozygous missense mutation, c.577-579delAAG heterozygous deletion mutation, c.247-248insCT heterozygous insertion mutation, c.659G > A heterozygous missense mutation, and a new variant locus c.1146_1146delT heterozygous deletion mutation in the four probands, respectively. In particular, c.1146_1146delT heterozygous deletion mutations not reported previously. Conservativeness and pathogenicity analyses confirmed that most of these amino acid residues were conserved, and all the mutations were found to be pathogenic. Analysis of protein modeling revealed that these mutations induced structural alterations in the protein or led to the formation of truncated proteins. According to the American College of Medical Genetics and Genomics (ACMG) classification criteria and guidelines for genetic variants, c.1146_1146delT was rated as pathogenic (PVS1 + M2 + PM4 + PP1 + PP3 + PP4). CONCLUSION: The identified mutations are likely associated with decreased PC levels in each of the four families. The clinical manifestations of hereditary PC deficiency exhibit considerable diversity.
Asunto(s)
Linaje , Deficiencia de Proteína C , Proteína C , Humanos , Deficiencia de Proteína C/genética , Deficiencia de Proteína C/complicaciones , Femenino , Masculino , Adulto , Proteína C/genética , Persona de Mediana Edad , Estudios Retrospectivos , Trombosis de la Vena/genética , Trombosis de la Vena/sangre , Mutación Missense , Embolia Pulmonar/genética , MutaciónRESUMEN
BACKGROUND AND OBJECTIVES: Deficiencies of protein C (PC) or protein S (PS) are rare diseases, characterized by mutations in the PC or PS genes, which encode plasma serine proteases with anti-coagulant activity. Severe PC or PS deficiencies manifest in early life as neonatal purpura fulminans, a life-threatening heamorrhagic condition requiring immediate treatment. First-line treatment involves replacement therapy, followed by maintenance with anti-coagulants. Replacement therapy with specific protein concentrates is currently only limited to PC, and therefore, a PC + PS concentrate represents a useful addition to therapeutic options, particularly for severe PS deficiency. Further, the production of a PC + PS concentrate from unused plasma fractionation intermediates would impact favourably on manufacturing costs, and consequently therapy prices for patients and health systems. MATERIALS AND METHODS: Several chromatographic runs were performed on the same unused plasma fractionation intermediates using different supports to obtain a PC/PS concentrate. The best chromatographic mediums were chosen, in terms of specific activity and recovery. A full process of purification including virus inactivation/removal and lyophilization steps was set up. RESULTS: The final freeze-dried product had a mean PC concentration of 47.75 IU/mL with 11% of PS, and a mean specific activity of 202.5 IU/mg protein, corresponding to over 12,000-fold purification from plasma. CONCLUSION: The development of a novel concentrated PC/PS mixture obtained from a waste fraction of other commercial products could be used for its potential therapeutic role in the management of neonatal purpura fulminans pathology.
Asunto(s)
Deficiencia de Proteína C , Púrpura Fulminante , Recién Nacido , Humanos , Púrpura Fulminante/tratamiento farmacológico , Púrpura Fulminante/genética , Deficiencia de Proteína C/tratamiento farmacológico , Proteína C/análisis , Proteína C/uso terapéutico , Proteína S , Plasma/químicaRESUMEN
Currently, limited information is available in the literature regarding the relationships between PROC mutations and clinical features in Chinese individuals. We aimed to characterize severe congenital Protein C deficiency in 22 unrelated Chinese families in a tertiary hospital by analyzing its clinical manifestation, associated risk factors, and gene mutations. We measured protein C activity and antigen levels for all participants, screened them for mutations in the PROC gene, and analyzed the clinical features of each family to identify commonalities and differences. The analysis revealed a total of 75 individuals with PCD and 16 different PROC mutations, including 12 missense mutations and 4 deletion mutations. Among them, 11 who were compound heterozygotes or homozygotes for mutations tended to develop symptoms at a younger age without any clear triggers. In contrast, the remaining 64 individuals who were heterozygotes for mutations often had clear triggers for their symptoms and experienced a milder course of the disease. It is worth noting that the mutation c.565C > T occurred most frequently, being identified in 8 out of 22 families (36%). Our team also reported five novel mutations, including c.742-744delAAG, c.383G > A, c.997G > A, c.1318C > T, and c.833T > C mutations. The identification of five novel mutations adds to the richness of the Human Genome Database. Asymptomatic heterozygotes are not uncommon, and they are prone to develop symptoms with obvious triggers. The evidence presented strongly suggest that asymptomatic individuals with family history of protein C deficiency can benefit from mutational analysis of PROC gene.
Asunto(s)
Deficiencia de Proteína C , Trombofilia , Humanos , Deficiencia de Proteína C/genética , Deficiencia de Proteína C/diagnóstico , Proteína C/genética , Proteína C/metabolismo , Mutación , Mutación MissenseRESUMEN
OBJECTIVES: To determine the optimal management for early-onset thrombophilia (EOT), the genetic and clinical features of protein C (PC)-, protein S (PS)-, or antithrombin (AT)-deficient patients of ≤20 years of age were studied in Japan. METHODS/RESULTS: Clinical and genetic information of all genetically diagnosed cases was collected through the prospective, retrospective study, and literature review. One-hundred-one patients had PC (n = 55), PS (n = 29), or AT deficiency (n = 18). One overlapping case had PC- and PS-monoallelic variant. Fifty-five PC-deficient patients (54%) had 26 monoallelic or 29 biallelic variant(s), and 29 (29%) PS-deficient patients had 20 monoallelic or nine biallelic variant(s). None of the patients had AT-biallelic variants. The frequent low-risk allele p.K193del (PC-Tottori) was found in five patients with monoallelic (19%) but not 29 with biallelic variant(s). The most common low-risk allele p.K196E (PS-Tokushima) was found in five with monoallelic (25%) and six with biallelic variant(s) (67%). One exceptional de novo PC variant was found in 32 families with EOT. Only five parents had a history of thromboembolism. Thrombosis concurrently developed in three mother-newborn pairs (two PC deficiency and one AT deficiency). The prospective cohort revealed the outcomes of 35 patients: three deaths with PC deficiency and 20 complication-free survivors. Neurological complications were more frequently found in patients with PC-biallelic variants than those with PC-, PS-, or AT-monoallelic variants (73% vs. 24%, p = .019). CONCLUSIONS: We demonstrate the need for elective screening for EOT targeting PC deficiency in Japan. Early prenatal diagnosis of PC deficiency in mother-infant pairs may prevent perinatal thrombosis in them.
Asunto(s)
Deficiencia de Antitrombina III , Deficiencia de Proteína C , Deficiencia de Proteína S , Trombofilia , Trombosis , Recién Nacido , Femenino , Embarazo , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Japón/epidemiología , Deficiencia de Proteína S/complicaciones , Deficiencia de Proteína S/diagnóstico , Deficiencia de Proteína S/genética , Trombofilia/complicaciones , Trombosis/etiología , Trombosis/genética , Deficiencia de Proteína C/genética , Deficiencia de Proteína C/complicaciones , Proteína C/genética , Anticoagulantes , Antitrombina III , AntitrombinasRESUMEN
Protein C deficiency is a rare blood disorder that increases the risk of thromboembolism, resulting in deep vein thrombosis, pulmonary embolisms and strokes. Segmental testicular infarction is also a rare condition with unclear aetiology. This case presents a man in his 50s with protein C deficiency who developed a segmental testicular infarction. The patient was managed conservatively, without surgical intervention. He was monitored with serial ultrasound, which demonstrated progression from normal testis to segmental infarction and eventually resolution. The case highlights that protein C deficiency can cause testicular infarction, and a multidisciplinary approach can help avoid unnecessary surgery with excellent outcomes. Segmental infarction should be considered in patients with pre-existing thrombophilias after excluding malignancy and infection. Conservative management with repeat ultrasonography and follow-up can be appropriate in such cases.
Asunto(s)
Deficiencia de Proteína C , Accidente Cerebrovascular , Enfermedades Testiculares , Masculino , Humanos , Deficiencia de Proteína C/complicaciones , Deficiencia de Proteína C/diagnóstico , Enfermedades Testiculares/etiología , Enfermedades Testiculares/complicaciones , Testículo/patología , Infarto/complicaciones , Accidente Cerebrovascular/complicacionesRESUMEN
The number of reports on genetic predisposition to pediatric thrombosis is increasing. The risk of thrombosis in childhood varies according to patient age, and the contribution of genetic predisposition also differs. The term early-onset thrombophilia, which occurs until the age of 20 years in patients with genetic diagnosis, was defined. Then, the registry in Japan was established. Further, publications were reviewed comprehensively, and results revealed the genetic and clinical characteristics of patients. Less than 60% of patients presented with protein C (PC) deficiency, and over half of them had PC-gene monoallelic variants. The number of patients with protein S or antithrombin deficiency increased with age. None of them were aged between 6 and 8 years. PC-Tottori and protein S-Tokushima, which are high-frequency and low-risk variants in Japanese, contributed to the development of thrombosis. However, PC-Tottori did not affect the development of severe PC deficiency. One exceptional de novo PC-deficient variant was identified in 32 EOT families, and thrombosis developed concurrently in three pairs of mothers-newborns. Appropriate EOT screening tests targeting PC deficiency are required to prevent maternal and neonatal thromboses.
Asunto(s)
Deficiencia de Proteína C , Trombofilia , Trombosis , Niño , Humanos , Lactante , Recién Nacido , Predisposición Genética a la Enfermedad , Medicina de Precisión , Trombofilia/genética , Trombofilia/diagnóstico , Deficiencia de Proteína C/diagnóstico , Deficiencia de Proteína C/genéticaRESUMEN
OBJECTIVE: To explore the genetic etiology for a fetus with hydrocephalus and intraventricular hemorrhage. METHODS: Trio whole exome sequencing was carried out. Candidate variants were verified by Sanger sequencing of the fetus and its parents. RESULTS: The fetus was found to harbor c.818G>A (p.W273X) and c.833T>C (p.L278P) compound heterozygous variants of the PROC gene, which were respectively inherited from its mother and father. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), both variants were predicted to be likely pathogenic (PVS1_Strong+PM2_Supporting+PP4; PM2_Supporting+PM3+PP1+PP3+PP4). CONCLUSION: The fetus was diagnosed with Protein C deficiency due to the c.818G>A (p.W273X) and c.833T>C (p.L278P) compound heterozygous variants of the PROC gene. Above finding has enriched the spectrum of PROC gene variants and enabled genetic counseling and prenatal diagnosis for the family.
Asunto(s)
Hidrocefalia , Deficiencia de Proteína C , Femenino , Embarazo , Humanos , Feto , Asesoramiento Genético , Genómica , Hidrocefalia/genética , MutaciónAsunto(s)
Hepatopatías , Deficiencia de Proteína C , Trombofilia , Trombosis de la Vena , Humanos , Deficiencia de Proteína C/complicaciones , Deficiencia de Proteína C/diagnóstico , Deficiencia de Proteína C/genética , Vena Porta , Trombosis de la Vena/complicaciones , Trombosis de la Vena/diagnósticoRESUMEN
BACKGROUND: Inherited protein C deficiency (PCD) caused by mutations in protein C (PC) gene (PROC) increases the risk of thrombosis. Missense mutations in PC's signal peptide and propeptide have been reported in patients with PCD, but their pathogenic mechanisms, except mutations in R42 residue, remain unclear. OBJECTIVES: To investigate the pathogenic mechanisms of inherited PCD caused by 11 naturally occurring missense mutations in PC's signal peptide and propeptide. METHODS: Using cell-based assays, we evaluated the impact of these mutations on various aspects such as activities and antigens of secreted PC, intracellular PC expression, subcellular localization of a reporter protein, and propeptide cleavage. Additionally, we investigated their effect on pre-messenger RNA (pre-mRNA) splicing using a minigene splicing assay. RESULTS: Our data revealed that certain missense mutations (L9P, R32C, R40C, R38W, and R42C) disrupted PC secretion by impeding cotranslational translocation to the endoplasmic reticulum or causing endoplasmic reticulum retention. Additionally, some mutations (R38W and R42L/H/S) resulted in abnormal propeptide cleavage. However, a few missense mutations (Q3P, W14G, and V26M) did not account for PCD. Using a minigene splicing assay, we observed that several variations (c.8A>C, c.76G>A, c.94C>T, and c.112C>T) increased the incidence of aberrant pre-mRNA splicing. CONCLUSION: Our findings suggest that variations in PC's signal peptide and propeptide have varying effects on the biological process of PC, including posttranscriptional pre-mRNA splicing, translation, and posttranslational processing. Additionally, a variation could affect the biological process of PC at multiple levels. Except for W14G, our results provide a clear understanding of the relationship between PROC genotype and inherited PCD.
Asunto(s)
Deficiencia de Proteína C , Humanos , Precursores del ARN/genética , Precursores del ARN/metabolismo , Señales de Clasificación de Proteína/genética , Empalme del ARN , Mutación , Mutación Missense , ARN Mensajero/genéticaRESUMEN
A 25-year-old man was diagnosed with diabetic ketoacidosis (DKA) at the onset of fulminant type 1 diabetes. After acute-phase DKA treatment including placement of a central venous catheter, a massive deep vein thrombosis (DVT) and pulmonary embolism (PE) were detected on hospital day 15. His protein C (PC) activity and antigen levels were low even 33 days after completing the DKA treatment, indicating partial type I PC deficiency. Severe PC dysfunction, due to overlapping of partial PC deficiency and hyperglycemia-induced PC suppression, concomitant with dehydration and catheter treatment, may have induced the massive DVT with PE. This case suggests that anti-coagulation therapy should be combined with acute-phase DKA treatment in patients with PC deficiency, even those who have been asymptomatic. As patients with partial PC deficiency should perhaps be included among those with severe DVT complications of DKA, venous thrombosis should always be considered as a potential complication of DKA.
Asunto(s)
Diabetes Mellitus Tipo 1 , Cetoacidosis Diabética , Deficiencia de Proteína C , Embolia Pulmonar , Trombosis de la Vena , Masculino , Humanos , Adulto , Diabetes Mellitus Tipo 1/complicaciones , Deficiencia de Proteína C/complicaciones , Trombosis de la Vena/complicaciones , Embolia Pulmonar/complicaciones , Cetoacidosis Diabética/complicaciones , Cetoacidosis Diabética/terapia , Factores de RiesgoRESUMEN
Protein C (PC) is a vitamin K-dependent zymogen synthesized in the liver that plays a major role in regulating the coagulation pathway. Upon interaction with the thrombin-thrombomodulin complex, PC is converted to its active form, activated PC (APC). APC complexes with protein S and regulates thrombin generation by the inactivation of Factors Va and VIIIa. The role of PC as a key regulator of the coagulation process is highlighted in the deficiency state, in which heterozygous deficiency of PC predisposes to an increased risk of venous thromboembolism (VTE), while in the homozygous deficiency state, potentially fatal complications in the fetus including purpura fulminans and disseminated intravascular coagulation (DIC) can occur. Protein C is often measured with other factors such as protein S and antithrombin as a screen in the investigation of VTE. The chromogenic PC assay, the protocol described in this chapter, quantitates the amount of functional PC in the plasma using an activator of PC with the degree of color change proportional to the amount of PC present in the sample. Other methods, including functional clotting-based assays and antigenic assays, are available; however, protocols for these assays will not be provided in this chapter.
Asunto(s)
Deficiencia de Proteína C , Tromboembolia Venosa , Humanos , Proteína C/metabolismo , Trombina/metabolismo , Anticoagulantes , Coagulación Sanguínea , Deficiencia de Proteína C/diagnósticoRESUMEN
BACKGROUND: Congenital protein C deficiency is a rare hereditary thrombophilia, neonatal purpura fulminans is the most serious form of this deficit. The purpose of this observation is two-fold. The first is the need to make an early diagnosis in order to improve the prognosis. The second, is to discuss the need. In case of extensive purpura fulminans in the neonatal period, the search for a deficiency in anticoagulant factor, in particular the dosage of protein C, in the newborn and in both parents. METHODS: The diagnosis is biological and is based on the quantitative determination of functionally active protein C. We use the Berichrom® Protein C assay on an automated coagulation analyzer from Siemens Healthcare Diagnostics, which allows the chromogenic determination of Protein C activity. RESULTS: We report an observation of cutaneous necrosis in a newborn having developed a purpura fulminans extensive secondary to a total congenital protein C deficiency. In front of this clinical picture, thrombophilia assessment is requested, revealing an isolated deficit in protein C < 1%. CONCLUSIONS: In the case of extensive purpura fulminans in the neonatal period, the search for a deficiency in anticoagulant factor, in particular the dosage of protein C, is essential in the newborn and in both parents.
Asunto(s)
Deficiencia de Proteína C , Púrpura Fulminante , Trombofilia , Recién Nacido , Humanos , Púrpura Fulminante/diagnóstico , Púrpura Fulminante/complicaciones , Deficiencia de Proteína C/complicaciones , Deficiencia de Proteína C/diagnóstico , Proteína C , Trombofilia/complicaciones , AnticoagulantesRESUMEN
BACKGROUND: Patients with Down syndrome are at a higher risk of developing autoimmune disorders such as thyroiditis, diabetes, and celiac disease compared with the general population. Although some diseases are well known to be associated with Down syndrome, others such as idiopathic pulmonary hemosiderosis and ischemic stroke due to protein C deficiency remain rare. CASE PRESENTATION: We report a case of a 2.5-year-old Tunisian girl with Down syndrome and hypothyroiditis admitted with dyspnea, anemia, and hemiplegia. Chest X-ray showed diffuse alveolar infiltrates. Laboratory tests showed severe anemia with hemoglobin of 4.2 g/dl without hemolysis. A diagnosis of idiopathic pulmonary hemosiderosis was confirmed by bronchoalveolar lavage showing numerous hemosiderin-laden macrophages, with a Golde score of 285 confirming the diagnosis of pulmonary hemosiderosis. Concerning hemiplegia, computed tomography showed multiple cerebral hypodensities suggestive of cerebral stroke. The etiology of these lesions was related to protein C deficiency. CONCLUSION: Idiopathic pulmonary hemosiderosis remains a severe disease, which is rarely associated with Down syndrome. The management of this disease in Down syndrome patients is difficult, especially when associated with an ischemic stroke secondary to protein C deficiency.