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Query: UMLS:C0021051 (
immunodeficiency
)
71,517
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Transcobalamin II
(TC II) is a serum protein responsible for transporting vitamin B12 to the cells. A previous observation of a child with congenital TC II deficiency and agammaglobulinemia suggested that this protein plays an important role in the immune response. Accordingly, TC II levels ere determined in 32 patients with autoimmune disease (AID) (i.e. 26 with lupus erythematosus, 4 with dermatomyositis, and 2 with autoimmune hemolytic anemia) and in 40 patients with acquired
immunodeficiency
due to chemotherapy. It was found that elevated TC II levels corresponded to active phases of AID. Changes in TC II levels correlated better with the clinical course of AID than complement, antinuclear antibody or native DNA binding capacity. This suggests that TC II could be a valuable parameter in following up activity of AID.
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PMID:[Increase of unsaturated transcobalamine II in autoimmune diseases; effect of immunosuppressive therapy (proceedings)]. 69 99
Zidovudine (formerly azidothymidine) is a potent inhibitor of the human
immunodeficiency
virus (HIV) reverse transcriptase and represents the first approved drug showing clinical efficacy in HIV-associated diseases. However, considerable toxicity causing
macrocytic anemia
, neutropenia, and myopathy has been reported, with severe mitochondrial alterations as a special feature of this myopathy. The mitochondrial changes are consistent with the fact that zidovudine acts as an inhibitor of the mitochondrial gamma-polymerase. Electron microscopically, we could confirm the presence of severely altered mitochondria in a 32-year-old male, who developed a necrotizing myopathy after daily administration of 1,000 mg zidovudine over a period of 15 months. In addition, there were even more severe nuclear changes that, for the most part, have not been documented electron microscopically in HIV-related myopathy either with or without zidovudine treatment, especially in non-necrotic and non-regenerating fibers. Since various in vitro studies have shown interference of zidovudine with nuclear DNA metabolism even in human cell lines, we assume that the nuclear changes that we observed are at least in part related to zidovudine treatment.
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PMID:Nuclear and mitochondrial changes of muscle fibers in AIDS after treatment with high doses of zidovudine. 128 95
The antiviral nucleoside analogue 2',3'-dideoxycytidine (ddC) is a DNA chain terminator and/or inhibitor of human
immunodeficiency
virus (HIV) reverse transcriptase. We evaluated the effects of ddC in 36 New Zealand white rabbits. Three/sex were assigned to a control group and 5 treatment groups (10-250 mg/kg/day) for 13 or 18 weeks. Blood samples were taken 1 week prior to treatment and weekly thereafter to termination with the exception of the 2 highest dose groups, where blood sample collection was terminated at week 13. Selected hematological analytes were measured weekly with the exception of prothrombin time (PT) and activated partial thromboplastin time (APTT). PT and APTT and selected biochemical analytes were measured prior to treatment, at 7 weeks, and after 13 weeks of treatment. All rabbits were necropsied. Giemsa and hematoxylin and eosin sections were prepared from methacrylate-embedded marrow. Hematological effects included decreases in red blood cell count, hemoglobin, hematocrit, and white blood cell count and increases in mean corpuscular volume and red cell distribution width. Platelets, platelet volume, PT, APTT, and mean corpuscular hemoglobin concentration values were variable or unchanged. Effects were dose-related, most were seen at 1 week, and they persisted to term. Bone marrow histopathologic changes included megalocytosis, erythroid hypoplasia, bizarre erythroid nuclear morphology, nuclear-cytoplasmic asynchrony, and increased mitotic figures. Lymphopenia caused by ddC plateaued at 2 weeks and persisted until termination. Heteropenia (neutropenia) was sporadic. Biochemical values for serum analytes were unchanged by treatment. The principal hematological effect of ddC upon the erythron was characterized as a nonregenerative
macrocytic anemia
with erythroid hypoplasia and megaloblastic erythropoiesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hematological effects of 2',3'-dideoxycytidine in rabbits. 133 36
Macaques chronically infected with simian
immunodeficiency
virus were treated with zidovudine (20 mg/kg of body weight per day for 9 weeks) or 3'-fluorothymidine (5 mg/kg of body weight per day for 9 weeks or three doses of 2 mg/kg per day for 24 days). Hematological changes in the treated animals included
macrocytic anemia
and leukopenia. Determination of antiviral effects in this model requires improved assay methods.
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PMID:Long-term tolerance and efficacy of 3'-azidothymidine and 3'-fluorothymidine treatment of asymptomatic monkeys infected with simian immunodeficiency virus. 141 63
The prophylactic and therapeutic properties of 3'-azido-3'-deoxythymidine (AZT) against simian
immunodeficiency
virus (SIV) infection were tested in four 3-month-old rhesus macaques. The infant monkeys were inoculated intravenously with a low dose (1 to 10 100% animal infectious doses) of uncloned SIVmac. The monkeys were treated orally with 50 mg of AZT per kg of body weight every 8 h; two animals were started on treatment 2 h prior to virus inoculation, and two animals were started on treatment 6 weeks later. All four animals were treated for a period of 6 to 10 weeks. Outward signs of AZT toxicity were absent, but a mild
macrocytic anemia
occurred soon after therapy was started and resolved shortly after it was discontinued. The two infants that were begun on AZT treatment 2 h prior to virus inoculation never became infected, as demonstrated by the inability to detect cell-free or cell-associated virus in the blood, proviral DNA in peripheral blood mononuclear cells, or anti-SIV antibodies. AZT administration over a 10-week period had no detectable effect on the course of disease in the two animals that were begun on treatment after the infection had been established. In addition to demonstrating the prophylactic effect of AZT against low-dose SIV exposure, the study demonstrated the ease with which infant rhesus macaques can be used for antiretroviral drug testing.
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PMID:Simian immunodeficiency virus (SIV) infection of infant rhesus macaques as a model to test antiretroviral drug prophylaxis and therapy: oral 3'-azido-3'-deoxythymidine prevents SIV infection. 148 81
This case study reported a 17-year-old female of common variable
immunodeficiency
(CVID) associated with bronchiectasis, pernicious anemia and mosaic trisomy 8. Clinically this patient presented with recurrent sinopulmonary infections, intractable diarrhea,
macrocytic anemia
, and primary amenorrhea. Immunological tests showed pan-hypogammaglobulinemia and a decrease of peripheral blood B cells (4%) and CD4+ cells (25%). Lymphoproliferative responses to mitogen (PHA) and specific antigen (BCG) were profoundly impaired in the patient in comparison to those in control. Production of interleukin 4 (IL-4) and gamma interferon (IFN-gamma) in the in vitro lymphoproliferation was also profoundly depressed. Pernicious anemia demonstrated by larger MCV (112.9 fl) and hyper-segmental granulocytes on peripheral blood smear responded to parental administration of vitamin B12. Interestingly, she had a mosaic trisomy 8 in peripheral blood mononuclear cells but normal 46XX karyotype in the bone marrow cells. To our knowledge, this is the first case of CVID associated with mosaic trisomy 8 reported in the literature. As the case exemplifies, CVID should be considered when the physicians evaluate the patient presenting with recurrent sinopulmonary infections, diarrhea, malnutrition, and pernicious anemia. It requires further study to explore whether the genes in the chromosome 8 are linked to CVID.
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PMID:Common variable immunodeficiency with mosaic trisomy 8: report of one case. 1119 41
The increased mortality observed when human
immunodeficiency
virus (HIV)-infected individuals are treated with clarithromycin (CLA) as prophylaxis for disseminated infection with organisms of the Mycobacterium avium complex (MAC) suggests that CLA might possess immunosuppressive activities. To test this possibility, we assessed the immunological response of BALB/c mice following subchronic (28 days) oral administration of CLA alone or in combination with zidovudine (ZDV). Because normal hematopoiesis is needed to maintain the immune system, we also examined the effect of these drugs given individually or in combination on several hematological parameters. The major effect of administration of 500 mg/kg CLA was a marked decrease in the lymphocyte/neutrophil ratio, and the only evidence of hematotoxicity in mice treated with 240 mg/kg ZDV alone was mild
macrocytic anemia
. However, treatment with a combination of CLA and ZDV resulted in severe hematotoxicity, evidenced by a significant (p < 0.01) decrease in the number of circulating erythrocytes, neutrophils, and lymphocytes and a 67% drop in splenic cellularity (p < 0.01). Treatment with CLA or ZDV alone or both drugs in combination had no effect on lymphocyte function, determined by measuring the ex vivo proliferative activity of splenocytes in response to alloantigens or a B cell mitogen, lipopolysaccharide (LPS). However, because of the cellular depletion in the spleen, overall immune responses in this organ decreased significantly (p < 0.05) in mice treated with CLA plus ZDV. These data suggest that interactions between CLA and ZDV warrant further evaluation because these drugs are given in combination to persons with advanced HIV infection.
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PMID:Prophylactic clarithromycin to treat mycobacterium avium in HIV patients receiving zidovudine may significantly increase mortality by suppressing lymphopoiesis and hematopoiesis. 1240 Aug 76
3'-Azido-3'-deoxythymidine (AZT) is the most widely used and evaluated chemotherapeutic agent for the treatment of persons with acquired immune deficiency syndrome (AIDS) and persons seropositive for human
immunodeficiency
virus (HIV). The National Cancer Institute nominated AZT for toxicity and carcinogenicity studies because of the impending large-scale use of AZT in the treatment of adult patients with AIDS or AIDS-related complex. alpha-Interferon A/D, which displays antiviral activity in mice, is a hybrid molecule composed of the N-terminal portion of human alpha-interferon A and the C-terminal portion of human alpha-interferon D. AZT and alpha-interferon A/D combination studies were conducted because in vitro studies of AZT and alpha-interferon have demonstrated that the combination is more effective in blocking HIV infection than either agent alone. Male and female B6C3F1 mice received AZT (approximately 98% pure) in 0.5% aqueous methylcellulose by gavage for 14 weeks or 2 years. In addition, male and female B6C3F1 mice received alpha-interferon A or alpha-interferon A/D by subcutaneous injection for 2 years, and male and female B6C3F1 mice received AZT in 0.5%% aqueous methylcellulose by gavage in combination with alpha-interferon A/D by subcutaneous injection for 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, mouse bone marrow erythrocytes, and mouse peripheral blood erythrocytes. 14-WEEK AZT STUDY: Groups of 10 male and 10 female mice received AZT in 0.5% methylcellulose by gavage at doses of 0, 50, 100, 200, 800, or 2,000 mg/kg daily for 14 weeks. Additional groups of 10 male and 10 female mice received AZT in 0.5% methylcellulose by gavage at doses of 0, 100, 800, or 2,000 mg/kg daily for 14 weeks and then were held without treatment for an additional 4 weeks before necropsy. One female receiving 100 mg/kg and two females receiving 200 mg/kg died during week 1 as a result of gavage trauma; one female receiving 2,000 mg/kg also died prior to the end of the 14-week dosing period. One female receiving 2,000 mg/kg in the recovery study also died from gavage trauma during week 1. The final mean body weights of dosed mice were similar to those of the vehicle control groups at the end of the dosing period and at the end of the recovery period. Female mice receiving 200, 800, or 2,000 mg/kg gained less weight than the vehicle controls during the 14-week dosing period. Exposure to AZT was toxic to the bone marrow, resulting in significant changes in the peripheral blood (decreased hematocrit values, erythrocyte counts, and hemoglobin concentrations, and increased mean cell volume and mean cell hemoglobin) and bone marrow (erythroid hypoplasia) characteristic of a dose- and time-dependent, minimal to moderate, poorly regenerative
macrocytic anemia
. At the end of the 4-week recovery period, the hematology parameters had returned to normal, indicating that the hematotoxicity was reversible. 2-YEAR STUDIES: AZT Groups of 95 male and 95 female mice received AZT in 0.5% methylcellulose by gavage at daily doses of 0, 30, 60, or 120 mg/kg body weight, administered as two equal doses at least 6 hours apart, 5 days per week for 105 weeks. Each group of 95 animals was composed of a core group of 50 animals for evaluation of carcinogenic response, a group of 30 animals for evaluation of hematology and bone marrow cellularity, and a group of 15 animals from which blood was drawn for determination of plasma AZT concentrations at week 54. alpha-Interferon A/D and AZT/alpha-Interferon A/D Studies Groups of 80 male and 80 female mice received AZT in 0.5% aqueous methylcellulose by gavage at daily doses of 0, 30, 60, or 120 mg/kg body weight, given in two equal doses, 5 days per week for 105 weeks. Those groups receiving AZT also received sub-cutaneous injections of 500 or 5,000 U alpha-interferon A/D three times per week for 105 weeks. Additional groups of 80 male and 80 female mice received subcutaneous injections of the vehicle, 500 U alpha-interferon A/D, 5,000 Uutaneous injections of the vehicle, 500 U α-interferon A/D, 5,000 U α-interferon A/D, or 5,000 U α-interferon A, three times per week for 105 weeks. Each group of 80 animals was composed of a core group of 50 animals for evaluation of carcinogenic response and a group of 30 animals for evaluation of hematology and bone marrow cellularity. Because of the large number of animals involved, the 2-year studies were started in four phases and, for clarity, are presented as follows: the AZT study, the α-interferon A/D study, the AZT/500 U α-interferon A/D study, and the AZT/5,000 U α-interferon A/D study. Design of the 2-year AZT, AZT/α-Interferon A/D, and α-Interferon A/D Studies AZT Dose AZT Study AZT/500 U α-Interferon A/D Study AZT/5,000 U α-Interferon A/D Study 500 or 5,000 U α-Interferon A/D or 5,000 U α-Interferon A Study Vehicle Control 95 male and 95 female micea 80 male and 80 female miceb 80 male and 80 female miceb 80 male and 80 female miceb 30 mg/kg AZT 95 male and 95 female mice 80 male and 80 female mice 80 male and 80 female mice none 60 mg/kg AZT 95 male and 95 female mice 80 male and 80 female mice 80 male and 80 female mice none 120 mg/kg AZT 95 male and 95 female mice 80 male and 80 female mice 80 male and 80 female mice none aFor the AZT study, there were 95 male and 95 female mice; these were divided into 50 males and 50 females in the core groups, 30 males and 30 females in the clinical pathology groups (hematology and bone marrow analyses only), and 15 males and 15 females for plasma AZT concentration determinations. bFor the α-interferon A/D study and the AZT/α-interferon A/D studies, there were 80 male and 80 female mice for each study; these were divided into 50 males and 50 females in the core groups and 30 males and 30 females in the clinical pathology groups (hematology and bone marrow analyses only). Survival and Body Weights Survival and mean body weights of mice exposed to AZT, α-interferon A, α-interferon A/D, or AZT plus α-interferon A/D were generally similar to those of the vehicle control groups. Hematology and Bone Marrow Analyses All groups of male and female mice receiving AZT exhibited changes in peripheral blood and bone marrow characteristic of a dose- and time-dependent, minimal to mild, macrocytic, nonresponsive anemia. In females, these changes were evident throughout the study. In males, the
macrocytic anemia
had resolved by week 80 in the 30 mg/kg group; at study termination erythrocyte macrocytosis was present only in males receiving 60 or 120 mg/kg AZT or AZT plus α-interferon A/D. There were no treatment-related alterations in hematology or bone marrow parameters in groups that received only α-interferon A or A/D. Pathology Findings Incidences of squamous cell carcinoma and squamous cell papilloma or carcinoma (combined) of the vagina occurred with a positive trend and were significantly increased in groups of female mice receiving 60 or 120 mg/kg AZT alone or in combination with α-interferon A/D. Epithelial hyperplasia was observed in all dosed groups of females, and the incidence was significantly increased in the 120 mg/kg AZT group. Three renal tubule adenomas and one renal tubule carcinoma were observed in male mice receiving 120 mg/kg AZT; the combined incidence in this group exceeded the range in historical controls. A renal tubule adenoma was observed in one male receiving 60 mg AZT/kg and 500 U α-interferon A/D; how ever, none were observed in other groups. Evaluation of step sections revealed a few more renal tubule hyperplasias but no additional neoplasms. The incidence of harderian gland adenoma was increased in male mice receiving 120 mg/kg AZT and exceeded the range in historical controls. Harderian gland neoplasms were observed in other groups but did not follow a treatment-related pattern. Overall Incidences of Vaginal Neoplasms and Hyperplasia of the Vaginal Epithelium in Female Mice in the 2-Year Gavage Studies of AZT and AZT/α-Interferon A/Da Vehicle Control 30 mg AZT/kg 60 mg AZT/kg 120 mg AZT/kg AZT alone 2/197 (1%)b 1/197 0/49 (0%) 3/49 5/45 (11%%) 4/45 11/49 (22%%) 11/49 500 U α-Interferon A/D 0/49 (0%%) 0/49 0/44 (0%) 4/44 5/48 (10%) 8/48 6/48 (13%) 12/48 5,000 U α-Interferon A/D 1/50 (2%) 1/50 1/48 (2%) 4/48 5/48 (10%) 8/48 4/50 (8%) 15/50 aData are presented as number of vaginal neoplasms/number of animals microscopically examined (first line) and number of vaginal hyperplasias/number of animals microscopically examined (second line) bCombined incidences of controls from the AZT alone study and the AZT/α-interferon A/D studies; incidences in the vehicle control group from the AZT alone study are 0/50 (0%%) (neoplasms) and 0/50 (hyperplasia) Overall Incidence of Harderian Gland Neoplasms in Male Mice in the 2-Year Gavage Studies of AZT and AZT/α-Interferon A/Da Vehicle Control 30 mg AZT/kg 60 mg AZT/kg 120 mg AZT/kg AZT alone 13/200 (6%%)b 5/50 (10%%) 2/50 (4%) 10/50 (20%%) 500 U α-Interferon A/D 3/50 (6%) 3/50 (6%) 1/50 (2%%) 4/50 (8%%) 5,000 U α-Interferon A/D 3/50 (6%) 9/50 (18%%) 4/50 (8%%) 4/50 (8%) aData are presented as number of harderian gland neoplasms/number of animals necropsied bCombined incidences of controls from the AZT alone study and the AZT/α-interferon A/D studies; incidence in the vehicle control group from the AZT alone study is 3/50 (6%) Male mice had a pattern of nonneoplastic liver lesions along with silver-staining helical organisms within the liver consistent with an infection with Helicobacter hepaticus. An organism compatible with H. hepaticus was confirmed by polymerase chain reaction-restriction fragment length polymorphism-based assays. Detection of dose-related differences in neoplasm incidences in these studies was not considered to have been significantly impacted by the infection with H. hepaticus or its associated hepatitis. GENETIC TOXICOLOGY: AZT is mutagenic in vitro and in vivo. It induced gene mutations in Salmonella typhimurium strain TA102, with and without S9; no increases in mutations were noted in the other tested strains of S. typhimurium. AZT induced sister chromatid exchanges, but not chromosomal aberrations, in cultured Chinese hamster ovary cells, with and without S9. In vivo studies with male mice administered AZT by gavage showed highly significant increases in micronucleated erythrocytes in bone marrow and peripheral blood after exposure periods that ranged from 72 hours to 14 weeks. CONCLUSIONS: Under the conditions of these 2-year gavage studies there was equivocal evidence of carcinogenic activity of AZT in male mice based on increased incidences of renal tubule and harderian gland neoplasms in groups receiving AZT alone. There was clear evidence of carcinogenic activity of AZT in female mice based on increased incidences of squamous cell neoplasms of the vagina in groups that received AZT alone or in combination with α-interferon A/D. Hematotoxicity occurred in all groups that received AZT. Treatment with AZT alone and AZT in combination with α-interferon A/D resulted in increased incidences of epithelial hyperplasia of the vagina in all dosed groups of females. Synonyms: AZT; 3'-azido-2',3'-dideoxythymidine; azidodeoxythymidine; azidothymidine; 3'-azidothymidine; 3'-deoxy-3'-azidothymidine; 3'-deoxy-(8CI) (9CI); BW A509U; Compound S; ZDV; zidovudine Trade name: Retrovir®
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PMID:NTP Toxicology and Carcinogenesis Studies of AZT (CAS No. 30516-87-1) and AZT/alpha-Interferon A/D B6C3F1 Mice (Gavage Studies). 1257 4
A 41-year-old human
immunodeficiency
virus (HIV)-positive man was hospitalized with complaints of a 4-week history of nausea and vomiting, associated with decreased oral intake, and a 4-day history of frontal headache and fever. His medical history was significant for a gunshot wound to the head 3 years prior, with a residual seizure disorder. He also had two previous hospitalizations, both for culture-negative bacterial meningitis; the first episode occurred 12 months before admission and the second episode occurred 5 months later. At that time, he was found to be positive for serum antibodies against HIV and a CD4+ T-lymphocyte count of 126/mm3. He had no known drug allergies and was not receiving any medication. On admission, the patient was febrile (104.0 degrees F) and hypotensive (blood pressure, 92/40 mm Hg). Pertinent physical examination findings included cachexia with bitemporal wasting, dry mucus membranes, adherent white patches on the oral mucosa, and negative Kernig's and Brudzinski's signs. His laboratory results revealed
macrocytic anemia
, a decreased serum sodium of 125 mEq/L, and a normal total leukocyte count with a CD4+ T-lymphocyte count < 50/mm3. Lumbar puncture opening pressure was elevated at 160 mm Hg, and cerebrospinal fluid analysis showed an increased white cell count of 97/microL (84% lymphocytes), a decreased glucose level of 26 mg/dL, and a decreased protein level of 42 mg/dL. The patient was started on empiric therapy that included intravenous ampicillin and cefotaxime, oral Bactrim, and clotrimazole lozenges for thrush. Cerebrospinal fluid culture was positive for Escherichia coli, sensitive to cefotaxime. Two days later, the patient developed fine, erythematous, nonblanchable macules primarily on his abdomen, with minimal involvement of his thorax and back. His skin lesions remained unchanged for the next 2 weeks. Repeat lumbar puncture was performed after 14 days of cefotaxime. The cerebrospinal fluid analysis showed an elevated white cell count of 7/microL (100% lymphocytes), a decreased glucose level of 53 mg/dL, and a decreased protein level of 33 mg/dL. The cerebrospinal fluid culture was now positive for Pseudomonas aeruginosa resistant to cefotaxime. The patient was started on imipenem. On day 34 of his admission, the patient became tachypneic with complaints of dyspnea. A chest roentgenogram revealed bilateral patchy infiltrates. He was transferred to the intensive care unit and intubated for hypoxemic respiratory failure (arterial blood gas values on 6 L of oxygen: pH, 7.46; bicarbonate, 23; and oxygen saturation, 37). That evening, the patient was also noted to have diffuse petechiae and purpura in a reticulated pattern over his abdomen (Figure 1A and 1B), most heavily concentrated in the periumbilical region, extending to the axillae and upper thighs. A 3x3-mm punch biopsy from abdominal skin demonstrated Strongyloides stercoralis larvae in the dermis (Figure 2A and 2B). His sputum specimen was teeming with adult S stercoralis worms (Figure 3) and, subsequently, numerous S stercoralis larvae were observed not only from the bronchoalveolar lavage but also from the nasogastric fluid specimen. These findings confirmed the diagnosis of disseminated strongyloidiasis. On hospital day 35, the patient was doing poorly and was started on thiabendazole (1250 mg twice daily for 28 days). Nine days later, ivermectin (4.5 mg once daily for 3 days for 2 courses) was also added. He continued to clinically deteriorate. The patient died 31 days after systemic antihelminthic treatment was initiated.
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PMID:Cutaneous manifestations of Strongyloides stercoralis hyperinfection in an HIV-seropositive patient. 2167 5
Objectives
Transcobalamin II
(TC) is an essential plasma protein for the absorption, transportation, and cellular uptake of cobalamin. TC deficiency presents in the first year of life with failure to thrive, hypotonia, lethargy, diarrhea, pallor, mucosal ulceration, anemia, pancytopenia, and agammaglobulinemia. Herein, we present TC deficiency diagnosed in two cases (twin siblings) with a novel variant in the TCN2 gene. Case presentation 4-month-old twins were admitted with fever, respiratory distress, vomiting, diarrhea, and failure to thrive. Physical examination findings revealed developmental delay and hypotonia with no head control, and laboratory findings were severe anemia, neutropenia, and hypogammaglobulinemia. Despite normal vitamin B12 and folate levels, homocysteine and urine methylmalonic acid levels were elevated in both patients. Bone marrow examinations revealed hypocellular bone marrow in both cases. The patients had novel pathogenic homozygous c.241C>T (p.Gln81Ter) variant in the TCN2 gene. In both cases, with intramuscular hydroxycobalamin therapy, laboratory parameters improved, and a successful clinical response was achieved. Conclusions In infants with pancytopenia, growth retardation, gastrointestinal manifestations, and
immunodeficiency
, the inborn error of cobalamin metabolism should be kept in mind. Early diagnosis and treatment are crucial for better clinical outcomes. What is new? In literature, to date, less than 50 cases with TC deficiency were identified. In this report, we presented twins with TCN2 gene mutation. Both patients emphasized that early and aggressive treatment is crucial for achieving optimal outcomes. In this report, we identified a novel variation in TCN2 gene.
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PMID:Transcobalamin II deficiency in twins with a novel variant in the TCN2 gene: case report and review of literature. 3284 Nov 61
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