Correlation of hyperplasia, splenomegaly and hepatomegaly with parasite population in BIO.LP-a mice infected with Leishmania donovani.

Congenic strain of BIO.LP-a male mice were experimentally infected with Leishmania donovani 3S strain from the spleen of a hamster donor. The weight ratio of spleen body, liver body and spleen liver calculated from the weight of six mice taken at weekly intervals for a period of 49 days showed that there is no hepatomegaly or splenomegaly during the first 14 days of infection when the parasite population increases. Maximum enlargement of liver and spleen was observed at day 35 postinfection, when the parasite population had declined to 11 per cent. Slight recovery was noted at day 49 with parasites reducing to 1 per cent. It is suggested that in endemic areas of human visceral leishmaniasis a search for amastigotes should be made from the biopsy of the liver or sternal puncture during the first phase of the disease when the patients suffer from a high fever with rigors. With the enlargement of liver and spleen due to proliferative response and infiltration of plasma cells, the parasite population disappears.     

Short report: occurrence of Leishmania donovani DNA in donated blood from seroreactive Brazilian blood donors

Human visceral leishmaniasis (kala-azar) transmitted by blood transfusion has been described in previous reports. Seroprevalence of antibodies to Leishmania donovani was shown to be related to prior blood transfusions in multiply transfused hemodialysis patients in Natal, Rio Grande do Norte, Brazil. In this study, a possible correlation between seroreactivity and the presence of L. donovani DNA was investigated in asymptomatic healthy blood donors. Sera were tested using the fucose mannose ligand (FML) ELISA, which was shown to have a sensitivity of 100%, a specificity of 96-100%, reliability, and diagnostic and prognostic potential for the detection of human and canine kala-azar, respectively. Leishmanial DNA was assessed by the polymerase chain reaction (PCR) and dot-blot hybridization techniques in blood and bone marrow samples. Among 21 FML-seroreactive asymptomatic blood donors, 5 (24%) were positive by the PCR and 9 (43%) were positive in a dot-blot assay of blood samples, showing a significant correlation (chi2 = 14.24, P < 0.01). No Leishmania DNA was detected in 20 FML non-reactive blood donors. Our results point to the need for control of transmission of kala-azar by blood transfusion in areas endemic for this disease.     

Mechanism of anaemia in resistant visceral leishmaniasis

We have studied the mechanism of a transfusion-dependent anaemia found in a two-year-old Maltese girl with visceral leishmaniasis that was resistant to multiple courses of antimonial therapy. Major factors contributing to the anaemia were haemolysis occurring in both the massively enlarged spleen and liver and haemodilution resulting from expansion of the plasma volume. There was no evidence of significant ineffective erythropoiesis, but a reduced plasma iron in the presence of greatly increased iron stores suggested that reticuloendothelial hyperplasia was accompanied by abnormal iron retention by macrophages typical of the 'anaemia of chronic disorders'. This may limit the erythropoietic response to anaemia in chronic visceral leishmaniasis.     

非疫源地黑热病2例资料分析

分析2例非疫源地黑热病病历资料。2例患者均有黑热病疫区生活史,且长期不规则发热,脾脏呈进行性肿大,肝脏肿大,白细胞计数降低,贫血,血小板减少等症状;骨髓检查显示网状吞噬型细胞多见,吞噬细胞内外可见利杜体,因此确诊为黑热病。予以对症治疗和葡萄糖酸锑杀虫治疗,患者发热症状消失,血细胞数回升,脾脏回缩,肝功能恢复,2例患者痊愈出院。     

Diffuse Nodular Regenerative Hyperplasia of the Liver Associated with Human Immunodeficiency Virus and Visceral Leishmaniasis

We present a patient with human immunodeficiency virus (HIV) infection coincident with diffuse nodular regenerative hyperplasia (DNRH) of the liver and visceral leishmaniasis. This association has not been previously described. Some DNRH cases are secondary to irregular blood flow in the liver. In the presently described case, there exist two possible conditioning factors for heterogenous distribution of blood flow: 1) the increased blood flow from splenomegaly, and 2) the irregular circulation of blood through sinusoids infiltrated by Leishmania -parasitized hyperplastic macrophages.     

Passive transfusion of human chorionic gonadotropin from plasma donated during pregnancy

Although fresh frozen plasma (FFP) prepared from autologous blood donated during pregnancy has frequently been given to homologous recipients at our institution, one transfusion resulted in an unanticipated diagnostic dilemma. A 31-year-old woman with disseminated intravascular coagulation of unclear etiology was transfused with multiple units of FFP, including 2 from pregnant autologous donors. A serum human chorionic gonadotropin (HCG) assay, performed because of the possibility that the patient's illness was a complication of unrecognized pregnancy, was positive using a blood sample drawn 7 h after the transfusions. An extensive evaluation was completed before the possibility of passive transfer of hormone from blood products was considered. Retrospective testing of serum samples established that HCG appeared in the patient's serum only after the first FFP transfusion from a pregnant autologous donor. In 8 other recipients of 1 or 2 units of FFP from pregnant autologous donors, post-transfusion HCG levels ranged between 96 and 1,750 mIU/ml. Of 15 recipients of packed red blood cells from pregnant autologous donors, only patients with renal failure or recipients of multiple units developed positive HCGs, which were always less than or equal to 85 mIU/ml. The differential diagnosis of a positive pregnancy test in a recently transfused individual should include the possibility of passively acquired hormone.     

A simple immune complex dissociation ELISA for leishmaniasis: Standardization of the assay in experimental models and preliminary results in canine and human samples

Visceral leishmaniasis, caused by Leishmania (Leishmania) chagasi, is a chronic parasitic disease of humans and dogs. Confirmation of the protozoal agent in bone marrow, lymph node or spleen aspirate is diagnostic, while specific-IgG serology is used mainly for epidemiology despite the general presence of high levels of serum immunoglobulin. Anecdotal reports of false-negative serology in active disease cases are known and are ascribed to the formation of immune complexes. Because dissociation of immune complexes can be accomplished by acid treatment, we devised a simple, routine enzyme immunoassay (ELISA) for the dissociation of immune complexes in serum samples using acid treatment in wells adsorbed with Leishmania antigen (dELISA). Confirmatory acid dot-blot was also developed for antigen detection by anti-Leishmania rabbit antiserum. In experimental L. chagasi hamster models, immune complexes interfered with ELISA mostly in the 30 and 60 days postinfection, according to both dELISA and antigen dot-blot results. In larger samples from endemic areas, dELISA was positive in 10% of seronegative dog samples (7/70) and 3.5% in negative human samples (3/88), showing that dELISA could be used in the serodiagnosis of visceral leishmaniasis. Moreover, dELISA could be used as an alternative approach to screening asymptomatic visceral leishmaniasis patients, instead of invasive confirmatory testing.     

The effect of blood transfusion on 51Cr-red blood cells surface-counting data in homozygous beta-thalassaemia.

The effect of blood transfusion on 51Cr-red blood cells surface-counting patterns was studied in 22 patients with homozygous beta-thalassaemia being transfused during erythrocyte survival study. Surface-counting patterns of 15 thalassaemics who had not been submitted to blood transfusion during the erythrocyte survival study were served as controls. In 17 of the transfused patients (group A), spleen excess counts (SEC) appeared decreasing after blood transfusion, reaching a minimum (about 50% of the initial value) 3-4 days later, and increasing thereafter to reach again their initial value on 8th to 10th posttransfusion day. The SEC pattern of the remaining 5 transfused patients (group B) presented a continuously ascending curve. Corresponding changes were observed in excess liver counts and heart counts patterns. As a result of these changes spleen/liver ratio (S/L) was found significantly affected by blood transfusion in the majority of thalassaemic patients which were transfused during the erythrocyte survival study. Furthermore, the mean age of group A patients (12.1 +/- 5.5 years) has been found to be significantly lower than that of group B (21.8 +/- 3.3 years). On the contrary, in the control group the SEC pattern appeared permanently increasing and the S/L was found unaltered during the whole duration of the erythrocyte survival study. In conclusion, as far as the surface-counting data represent indexes for splenectomy in thalassaemic patients, the results of this study signify that the influence of blood transfusion on these has to be taken into account.     

Role of spleen in hereditary spherocytosis: evidence for increased in vitro proteolysis of red cell membrane

In vitro proteolysis of red cell membranes has been studied by means of electrophoretic separation on SDS-polyacrylamide gel of solubilized ghost proteins and subsequent densitometry of separated, stained bands; the amounts of major membrane proteins were measured in ghosts either with inhibited or with allowed proteolysis in the following cases: 15 patients suffering from hereditary spherocytosis (HS) with variable degree of spleen enlargement, eight cirrhotic patients with spleen enlargement and 12 healthy blood donors as control group. Proteolysis was present to a greater extent in HS patients with larger splenomegaly, lesser in HS with smaller splenomegaly, and was comparable to healthy controls both in splenectomized HS and in patients with spleen enlargement due to liver cirrhosis. The results suggest the involvement of splenomegaly in the enhancement of in vitro proteolysis in HS red cell membrane; it is probably attributable to joint effects of the damage induced in red cells by prolonged retention within haemolysing spleen together with the abnormalities genetically affecting the structure of HS red cell membrane.     

The influence of dose of transfusion and component of blood on the incidence of post-transfusion hepatitis

Two thousand five hundred ninety-six consecutive patients who received blood transfusion for the first time within one week and had no liver dysfunction before transfusion had been selected from 8637 patients who received blood transfusion at the hospital between 1982 and 1987. The influence of dose, components of transfused blood and sex, age of recipients on the incidence of post-transfusion hepatitis was investigated. The rate of development of hepatitis depended on the dose of transfusion, not on sex and age of recipients. The rate of development of hepatitis raised as number of transfused blood increased without limiting point to 100%. The carrier rate of healthy population of non-A, non-B hepatitis virus was estimated 1.39%. Stored blood, concentrated red blood cell and fresh blood are high risk components and fresh frozen plasma was low risk component.     

Transmission of Leishmania infantum MON-98 to hamsters by the bite of Phlebotomus langeroni Nitzulescu (Diptera: Psychodidae)

The ability of Phlebotomus langeroni to successfully acquire and transmit Leishmania infantum MON-98 to hamsters was demonstrated. Sand flies and Leishmania both originated from an infantile visceral leishmaniasis focus in El Agamy Egypt. P. langeroni females were infected by feeding on lesions of needle-inoculated hamster and on infected blood suspension using a chick-skin membrane apparatus. Infection rate of sand flies fed on membrane was 88% compared to 7.8% for flies fed on leishmanial lesion. The transmission to hamster took place by the bites of infective flies taking a second blood meal, on the 8th to 10th day post-feeding. Furthermore, successful transmission was by the bites of flies that took no blood or that took full blood meal. Whereas flies that took full blood meal were not infective as indicated by dissection. In three hamsters, lesions developed after three months. Leishmania amastigotes were demonstrated from the lesion as well as from the liver and spleen of infected hamsters.     

Albumin-quercetin combination offers a therapeutic advantage in the prevention of reduced survival of erythrocytes in visceral leishmaniasis

Visceral leishmaniasis is associated with the reduced survival of erythrocytes, the cause of which remains to be fully explored. Here, we described the mechanism underlying the shortened lifespan of erythrocytes in visceral leishmaniasis and proposed a combination therapy with quercetin and hamster serum albumin towards its rectification. Decreased redox potential in erythrocytes followed by oxidative denaturation of hemoglobin and pathologic association of iron with the cell membrane facilitated premature hemolysis during leishmanial infection. Recently, we have reported the therapeutic efficacy of quercetin in arresting the enhanced destruction of erythrocytes in visceral leishmaniasis. Since serum albumin, the principal carrier protein for quercetin gets depleted in visceral leishmaniasis, the situation may compromise the efficacy of quercetin in this disease. We now report the use of quercetin-hamster serum albumin combination to increase the bioavailability of quercetin. The combination targeted hemoglobin oxidation and produced an effective attenuation of heme degradation. This led to decreased iron decompartmentalization, thereby increasing the life span of erythrocytes during leishmanial infection. Thus, we speculate that suppression of iron decompartmentalization, with the combination of quercetin and serum albumin might be a new approach in the prevention of reduced survival of erythrocytes in visceral leishmaniasis.     

A Comparative Study of Hypersplenism in Reactive and Congestive Splenomegaly

S ummary . Anaemia, leucopenia, and thrombocytopenia due to hypersplenism have been compared in 75 patients. Forty-six patients had congestive splenomegaly due to portal hypertension. Twenty-nine patients had reactive splenomegaly due in 27 to idiopathic tropical splenomegaly, and in two to visceral leishmaniasis. The only definite difference between the two groups was a lesser degree of lymphopenia in patients with reactive splenomegaly. It is suggested that this difference may be explained by an increase in production of lymphocytes in idiopathic tropical splenomegaly and that manifestations of hypersplenism are not directly influenced by histological or haemodynamic differences within the enlarged spleen.     

The effect of blood transfusion on 51Cr-red blood cells surface-counting data in homozygous β-thalassaemia

Summary The effect of blood transfusion on ⁵¹Cr-red blood cells surface-counting patterns was studied in 22 patients with homozygous β-thalassaemia being transfused during erythrocyte survival study. Surface-counting patterns of 15 thalassaemics who had not been submitted to blood transfusion during the erythrocyte survival study were served as controls. In 17 of the transfused patients (group A), spleen excess counts (SEC) appeared decreasing after blood transfusion, reaching a minimum (about 50% of the initial value) 3–4 days later, and increasing thereafter to reach again their initial value on 8th to 10th post-transfusion day. The SEC pattern of the remaining 5 tranfused patients (group B) presented a continuously ascending curve. Corresponding changes were observed in excess liver counts and heart counts patterns. As a result of these changes spleen/liver ratio (S/L) was found significantly affected by blood transfusion in the majority of thalassaemic patients which were transfused during the erythrocyte survival study. Furthermore, the mean age of group A patients (12.1 ± 5.5 years) has been found to be significantly lower than that of group B (21.8 ± 3.3 years). On the contrary, in the control group the SEC pattern appeared permanently increasing and the S/L was found unaltered during the whole duration of the erythrocyte survival study. In conclusion, as far as the surface-counting data represent indexes for splenectomy in thalassaemic patients, the results of this study signify that the influence of blood transfusion on these has to be taken into account.     

Prevalence of TT virus before and after blood transfusion in patients with chronic liver disease treated surgically for hepatocellular carcinoma

BACKGROUND: To examine the prevalence of TT virus (TTV) before and after blood transfusion, we retrospectively examined serum samples obtained from 55 patients who received blood transfusions before, during and after resection of hepatocellular carcinoma. METHODS: TT virus DNA was extracted from serum samples and detected by nested polymerase chain reaction. Before transfusion, seven (12.7%) were positive for TTV. Patients were transfused whole blood or separated blood components (fresh frozen plasma, platelet and/or red blood cells), the total amount of transfused fresh frozen plasma ranging from 12 to 271 (median 38) units. RESULTS: Seven (14.6%) of the 48 TTV-negative patients became positive for TTV-DNA 1 month after transfusion. Only one of the seven patients, who was already positive for HCV-RNA, exhibited elevation of alanine aminotransferase. Five of the newly infected seven patients become negative for TTV during a 2 year follow up. CONCLUSIONS: Our findings suggest that the proportion of patients with TTV was relatively high in this sample, and that the prevalence of TTV transmission by blood components was also relatively high (14.6%). Although TTV persisted for more than 6 months in some patients, infection was not noticeable during the course of chronic liver disease.     

Marked improvement of platelet transfusion refractoriness after bortezomib therapy in multiple myeloma

We report a patient with refractory multiple myeloma (MM) who developed platelet transfusion refractoriness (PTR). A 61-year-old woman was diagnosed with MM in July 2003. She underwent high-dose chemotherapy followed by autologous stem cell transplantation, and achieved a very good partial response. However, she relapsed in June 2006, and was referred to our hospital in October of the same year. Laboratory examinations showed pancytopenia and increased plasma cells in the peripheral blood. Platelet transfusions from random donors became ineffective, and anti-HLA class I antibody (83.8% positive) was detected in the serum by flow cytometry assay (Flow PRA). Therefore, she was considered to have developed PTR due to anti-HLA class I antibody caused by the previous blood transfusions. She was transfused with HLA-matched platelets, and then treated with bortezomib plus dexamethasone (BD) for refractory MM. The serum IgG level decreased from 7,451 to 1,735 mg/dL, and HLA class I antibody was markedly decreased to 1.9%. In addition, platelet transfusion from random donors showed clinical effects after BD therapy. This case suggests that bortezomib might be effective in different types of immune disease by inhibiting allo-reactive antibody.     

A simple,practical model for reducing alloimmunization in patients with sickle cell disease

Patients with sickle cell disease (SCD) form immune alloantibodies more frequently than other transfused populations because red cells (RBCs) from white donors (with a higher incidence of certain Rh, Duffy, Kell, and Kidd blood group antigens) are transfused to black patients often lacking these antigens. We propose a model to reduce alloimmunization in patients with SCD by providing them with blood from only black random donors. Rationale is shown by examining calculations based on the phenotype E–, C–, Fy(a–), K–, and Jk(b–). There is a 7% probability that this phenotype belongs to a white donor, while there is a 93% probability that this phenotype belongs to a black donor. The probability of selecting blood from a black donor identical with the above phenotype for black recipients from an all black population and from a typical urban blood inventory population (90% white, 10% black) is 1/4 and 1/33, respectively. Therefore, an 8-fold greater chance of selecting antigen non-identical blood occurs if blood is obtained from a typical urban donor population as compared to a black population. Based on these calculations, alloimmunization can be reduced prospectively in patients with SCD by meeting their transfusion requirements with blood selected from random black blood donors.     

Anti-leishmanial activity of a new formulation of amphotericin B

The effectiveness of albumin microspheres loaded with amphotericin B was tested in an in vivo model of visceral leishmaniasis using the golden hamster. Free and encapsulated amphotericin B was tested at the dose of 1 mg/kg given by the intracardiac route on days 25, 26 and 27 post-infection (p.i.) to treat animals previously infected with 10(7) stationary promastigotes by the intracardiac route. Encapsulated amphotericin was highly effective against infection causing a reduction of 88.8% and 87.2% in the early stage of infection (day 32 p.i.) and of 66.7% and 54% in a later stage of infection (day 135 p.i.) in liver and spleen parasite load respectively, compared with untreated animals, whereas free amphotericin was inactive. Lymphocyte proliferation was restored together with an increase in CD4(+) subsets in animals treated with encapsulated amphotericin B, but not in those treated with the non-encapsulated compound. Antibody responses did not increase after treatment with encapsulated amphotericin B with antibody levels remaining at base levels for most animals in contrast to those of untreated or treated with free amphotericin, where in most animals the antibody levels sharply increased. This new formulation could be a more economical alternative to liposomes for the treatment of visceral leishmaniasis with amphotericin B.     

Increased natural killer activity does not prevent progression of experimental kala-azar

Kala-azar is the visceral form of leishmaniasis and it is caused by intracellular parasites from the complex Leishmania donovani. Golden hamster (Mesocricetus auratus) infected with Leishmania donovani develop a disease very similar to human Kala-azar. There is conspicuous hipergammaglobulinaemia and their T cells do not respond to stimulation with parasite antigens. We used this experimental model to evaluate the natural killer (NK) activity during the initial phase of the disease. Outbred hamsters infected by intravenous route with 5.10(6) amastigotes of L. donovani 1S showed a concurrent increase in the spleen weight and in the spleen cell number. Using the single cell assay we detected a significant increase in the percentage of NK effector cells on the 4th day of infection. Imprints from spleen and liver showed at days 14 and 28 a significant increase in the parasite burden. These results show that the increased NK activity in the beginning of the infection was not able to restrain the progression of the disease in this experimental model.     

我国黑热病的流行概况和防治现状

黑热病又称内脏利什曼病,是严重危害人类身体健康的寄生虫病。按传染源特点可分为野生动物源型、犬源型和人源型3种类型。目前,人源型黑热病除新疆流行区外,在其他流行区已得到控制。而犬源型和野生动物源型黑热病则在其流行区不断出现,有死灰复燃之势。本文对我国黑热病的分型、流行概况和防治现状进行了综述。