Post-hepatitis primary disease does not influence 6-year survival after liver transplantation beyond 1 year

Orthotopic liver transplantation (OLT) is used as a definitive treatment for end-stage liver disease and prolonged posttransplant survival has already been reported. The incidence of late mortality and graft morbidity is, however, not well defined and the role of primary viral disease in the long-term follow-up results is not clear. Data of posttransplant follow-up in 213 patients, 156 adults and 57 children, who survived at least 1 year were reviewed in order to define causes of graft dysfunction, graft loss and death. In 98 patients, 103 persistent graft dysfunctions were found. Thirty-four grafts were later lost [28 deaths and 6 successful retransplantations (re-OLT)]. The results were reviewed grouping patients according to their age and viral hepatitis status at the time of the transplantation. HBV-positive patients (51) showed 4 re-OLT (1 HBV), 3 liver-related deaths (2 HBV), 24 graft dysfunctions (8 HBV, 5 HCV), and 85.2% 6-year survival (based on 100% survival at 1 year). HCV-positive adults (28) showed 1 re-OLT, 3 HCV-related deaths, 24 graft dysfunctions (19 HCV), and 68.8% 6-year survival. HBV-HCV-positive patients (14) showed no graft loss and death, 10 graft dysfunctions (7 HCV, 1 HBV, 2 HBV-HCV), and 81.8% 6-year survival. HBV-HCV-negative adults (63) showed 3 non-hepatitis-related re-OLT, 5 liver-related deaths (2 HCV), 24 graft dysfunctions (6 HCV, 2 HBV), and 83.1% 6-year survival. HBV-HCV-negative children (49) showed no re-OLT, 1 HCV-related death, 14 graft dysfunctions (3 HCV), and 92.6% 6-year survival. HCV-positive children (8) showed 1 HCV-related re-OLT, 2 HCV-related deaths, 4 graft dysfunctions (3 HCV), and 81.3% 6-year survival. The main cause of graft dysfunction was hepatitis (45 HCV and 13 HBV), followed by technical complications (21), rejection (16), recurrent alcoholism (3), HIV infection (1), and unknown causes (4). In this long-term post-transplant follow-up series, viral hepatitis led to graft dysfunction in 58/103 (56.3%) cases, late graft failure was viral hepatitis-related in 11/ 20 (55%) cases, and, as a total, HCV infection was present in 45/58 (77.5%) cases of viral hepatitis-related graft damage. Looking at the timing of hepatitis-related graft failure, in 70% of cases death occurred after the 5th post-transplant year. In our experience, the occurrence of hepatitis, particularly HCV induced, was common and led to abnormal graft function, but the 6-year post-transplant survival (based on 100% survival at 1 year) in patients surviving for at least 1 year did not differ on the basis of the pretransplant viral hepatitis status. This finding may be consistent with the slow progression of the viral damage and longer follow-up results remain to be established. Nevertheless, data from the present study suggest that in long-term liver transplant survivors, the risk of deteriorating liver damage and eventual failure after 5 years remains only in those patients experiencing a viral hepatitis infection.

Mechanisms of microsporidial cell division: ultrastructural study on Encephalitozoon hellem

The mitotic process in microsporidian Encephalitozoon hellem, a known human pathogen, has been studied with the aim of elucidating some ultrastructural aspects of its nuclear division. The presence of a nuclear spindle, of "electrondense spindle plaques" associated with the nuclear envelope and of cytoplasmic double walled vesicles are reported. We suggest that these "electrondense spindle plaques" serve as foci for intranuclear and cytoplasmic microtubule arrangements, similar to the microtubule organizing centers within the centrosomes of animal cells. The extent to which the microsporidial division process is comparable with that of more familiar eukaryotes such as yeast cells is discussed.

Mediterranean leishmaniasis in HIV-infected patients: epidemiological, clinical, and diagnostic features of 22 cases

Twenty-two Italian HIV-infected patients developed leishmaniasis, clinically manifested as visceral (13 cases), cutaneous (2 cases) and disseminated disease (7 cases). Twenty were males and two females (mean age: 32.8 years) with a mean CD4+ cell count of 46.8/microliter at diagnosis; risk factors were intravenous drug use (17 patients) and sexual behaviour (two bisexual, two homosexual, one heterosexual). All but one patient lived or travelled in hypoendemic Italian regions and other Mediterranean countries. Apart from the two patients with cutaneous leishmaniasis, the clinico-pathological and biological spectrum of the infection was often atypical, especially in patients with disseminated disease. The diagnosis was routinely made by direct recovery of parasites in biological specimens, mainly in bone marrow aspirate, whereas serology was negative or borderline in most of the patients. Among 17 in vitro isolates, Leishmania infantum was the only species involved with previously undescribed isoenzyme patterns in two cases. Treatment with antimonials and other drugs showed only temporary clinical improvement in some patients. Relapses were the rule. Leishmaniasis confirms itself as an opportunistic infection in HIV-positive persons. Secondary chemoprophylaxis should be considered in cases of relapsing disease.

A survey of amoebic infection in the Wonji area of central Ethiopia

An epidemiological survey to characterize Entamoeba histolytica/E dispar isolates from 123 human subjects was carried out in the Wonji area of Central Ethiopia, where an increased incidence of amoebic infection has been reported. In a randomized, coproparasitological study, 93 (75.6%) of the subjects were found positive for at least one species of intestinal parasite: 14 (15.1%) harboured only one species and 79 (84.9%) were infected with at least two species. In-vitro culture in Robinson's medium revealed amoebic parasites in 52 (82.5%) of the 63 cases tested. Of the 29 amoebic isolates successfully stabilized, cloned and characterized by Sargeaunt's electrophoretic technique, 27 (93.1%) were of E. dispar zymodemes (19 of zymodeme I, two each of zymodemes III, V and XI, and one each of zymodemes X and XV) and two (6.9%) were of E. histolytica (zymodeme XIII).

Asymptomatic respiratory tract microsporidiosis due to Encephalitozoon hellem in three patients with AIDS

Microsporidia of the genera Enterocytozoon and Encephalitozoon have been identified as frequent causes of intestinal and disseminated infections, respectively, in patients with AIDS. Even though most subjects infected with these protozoa develop overt disease, simple colonization without illness may occur, as we observed in three severely immunosuppressed patients with AIDS. The parasites, recognized in and isolated from bronchoalveolar lavage sediment specimens, were characterized as Encephalitozoon hellem. Colonization of the bronchial tree was temporary, and treatment with albendazole was not needed to clear the infection.

Ultrastructural features of spindle microtubule organization during the nuclear division of Encephalitozoon hellem

Ultrastructural studies were carried out to describe the nuclear division cycle of a strain of Encephalitozoon hellem isolated from an Italian AIDS patient. The nuclear division occurs during the proliferative vegetative phase and it is characterized by the intranuclear mitosis and by the lack of centrioles. The spindle termini are electron dense spindle plaques (ESPs), resembling to the spindle pole bodies (SPBs) of Saccharomycetes. The ESPs are bifacial organella forming microtubules on both nucleoplasic and cytoplasmic faces. In the outer layer of the spindle plaque are present vesicular elements lined by a double membrane of unknown function. The peculiar morphological features of E. hellem ESPs indicate that both intranuclear spindle and cytoplasmic microtubules are involved in the nuclear division.

Cloning and recombinant expression of rat and human kynureninase

Kynureninase [E.C.3.7.1.3.] is one of the enzymes involved in the biosynthesis of NAD cofactors from tryptophan through the kynurenine pathway. By tryptic and CNBr digestion of purified rat liver kynureninase, we obtained about 28% of the amino acid sequence of the enzyme. The rat kynureninase cDNA, isolated by means of reverse-transcribed polymerase chain reaction and hybridization screening, codes for a polypeptide of 464 amino acids. Northern blot analysis revealed the synthesis of a 2.0 kb rat kynureninase mRNA. A cDNA encoding human liver kynureninase was also isolated. The deduced amino acid sequence is 85% identical to that of the rat protein. COS-1 cells were transfected with both cDNAs. The Km values of the rat enzyme, for L-kynurenine and DL-3-hydroxykynurenine, were 440 +/- 20 microM and 32 +/- 5 microM and of the human enzyme 440 /- 20 microM and 49 +/- 6 microM, respectively. Interestingly, COS-1 cells transfected with the cDNA coding for rat kynureninase also display cysteine-conjugate beta-lyase activity.