The recombinant protein rSP03B is a valid antigen for screening dog exposure to Phlebotomus perniciosus across foci of canine leishmaniasis.

The frequency of sandfly-host contacts can be measured by host antibody levels against sandfly salivary proteins. Recombinant salivary proteins are suggested to represent a valid replacement for salivary gland homogenate (SGH); however, it is necessary to prove that such antigens are recognized by antibodies against various populations of the same species. Phlebotomus perniciosus (Diptera: Psychodidae) is the main vector of Leishmania infantum (Trypanosomatida: Trypanosomatidae) in southwest Europe and is widespread from Portugal to Italy. In this study, sera were sampled from naturally exposed dogs from distant regions, including Campania (southern Italy), Umbria (central Italy) and the metropolitan Lisbon region (Portugal), where P. perniciosus is the unique or principal vector species. Sera were screened for anti-P. perniciosus antibodies using SGH and 43-kDa yellow-related recombinant protein (rSP03B). A robust correlation between antibodies recognizing SGH and rSP03B was detected in all regions, suggesting substantial antigenic cross-reactivity among different P. perniciosus populations. No significant differences in this relationship were detected between regions. Moreover, rSP03B and the native yellow-related protein were shown to share similar antigenic epitopes, as canine immunoglobulin G (IgG) binding to the native protein was inhibited by pre-incubation with the recombinant form. These findings suggest that rSP03B should be regarded as a universal marker of sandfly exposure throughout the geographical distribution of P. perniciosus.

The burden of visceral leishmaniasis in Italy from 1982 to 2012: a retrospective analysis of the multi-annual epidemic that occurred from 1989 to 2009.

Starting from 1989 Italy experienced an increase of visceral leishmaniasis (VL) cases over a baseline of 10 to 30 cases reported annually. The number of cases peaked in 2000 and 2004 with more than 200 cases/year, and subsequently declined to reach on average one third of the 2000 peak value in the period after 2010. A retrospective analysis from 1982 to 2012 showed that the multi-annual epidemic consisted of major components including (i) an outbreak involving infants and immunocompetent adults in parts of the Campania region (southern peninsular Italy) and that appears to have declined naturally, (ii) a second outbreak affecting human immunodeficiency virus (HIV)-infected individuals throughout the country, that declined owing to the use of highly active antiretroviral therapies (HAART), (iii) a generalised increase of VL cases in immunocompetent individuals and patients affected by associated conditions other than HIV from endemic regions of peninsular and insular Italy (other than Campania), which was due to a geographical spreading of VL foci, with no major case-clusters or outbreak features. A minor component consisted in the appearance of a few autochthonous cases in formerly non-endemic areas, starting from the early 1990s. Epidemic determinants and reasons for VL decline in the Campania region remain largely unexplained, despite the information available on canine reservoir and phlebotomine vectors in Italy.

Ongoing outbreak of visceral leishmaniasis in Bologna Province, Italy, November 2012 to May 2013.

An increased number of autochthonous visceral leishmaniasis (VL) cases has recently been reported in Bologna Province in northern Italy. Over six months from November 2012 to May 2013, 14 cases occurred, whereas the average number of cases per year was 2.6 (range: 0-8) in 2008 to 2012. VL was diagnosed in a median of 40 days (range: 15-120) from disease onset. This delay in diagnosis shows the need for heightened awareness of clinicians for autochthonous VL in Europe.

Seasonal phenology, host-blood feeding preferences and natural Leishmania infection of Phlebotomus perniciosus (Diptera, Psychodidae) in a high-endemic focus of canine leishmaniasis in Rome province, Italy.

A 2-year survey aimed to study seasonal phenology, host-blood feeding preferences and Leishmania infections of Phlebotomus perniciosus, was carried out in a high-endemic focus of canine leishmaniasis in Rome province, Italy. Sandfly densities were monitored by sticky traps, while CDC light traps and hand collections were used for individual sandfly analyses. Four species were identified, three belonging to Phlebotomus (P. perniciosus, Phlebotomus mascittii and Phlebotomus papatasi) and one to Sergentomyia (Sergentomyia minuta) genera. In sticky traps, P. perniciosus (53.5%) and S. minuta (46.0%) were the prevalent species, whereas specimens collected by CDC light traps and hand collections consisted mostly of P. perniciosus. The study showed a markedly different sandfly density between 2003 and 2002 collections (5024 specimens versus 644 specimens, respectively), which was attributed to different climatic conditions. In 2003 adults were active during 7 months (May-November) with a typical bimodal distribution, while in 2002 their activity was shorter (5 months, June-October) without clear density peaks. In this low-density year, the prevalence of P. perniciosus was significantly higher in domestic than in wild resting sites. Blood meal tests showed that P. perniciosus had no preferences for any of the two Leishmania susceptible hosts, being the forage ratio rate 0.7 and 1.0 for man and dog, respectively. A significant number of P. perniciosus was found with avian (60.3%) or ovine (24.2%) blood, that was in relation with the habitats where fed specimens were collected. The rate of specimens of P. perniciosus without blood and found positive for Leishmania DNA, detected by a sensitive nested-PCR technique, was much higher (27.6%) than the promastigote infection rate determined by microscopy in the dissected females (1.4%). The intense Leishmania transmission in the study area was confirmed by the high prevalence of anti-leishmanial antibodies in dogs (33.3%).

NO donors inhibit Leishmania infantum cysteine proteinase activity.

Nitric oxide (NO) releasing drugs (e.g., glyceryl trinitrate) were successfully used in the treatment of cutaneous leishmaniasis in man. In the present study, the effect of NO donors on the catalytic activity of the cysteine proteinase from promastigotes of Leishmania infantum, an agent of Old World visceral and cutaneous leishmaniases, is reported. In particular, one equivalent of NO, released by the NO donors S-nitrosoglutathione, glyceryl trinitrate, (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide, 3-morpholinosydnonimine, S-nitrosoacetylpenicillamine and sodium nitroprusside, inhibited one equivalent of the parasite cysteine proteinase. As expected, NO-deprived compounds did not affect the catalytic activity of the parasite cysteine proteinase. Furthermore, the absorption spectrum of the (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide-treated inactive L. infantum enzyme displayed a maximum in the 330-350 nm wavelength range. The reducing agents dithiothreitol and L-ascorbic acid completely prevented parasite cysteine proteinase inhibition by NO, fully restored the catalytic activity, and reversed the NO-induced absorption spectrum of the inactive enzyme. Moreover, S-nitrosoacetylpenicillamine displayed a leishmanicidal effect, inhibiting the cysteine proteinase activity in vivo. As expected, the NO-deprived compound N-acetylpenicillamine did not affect significantly the parasite viability and the enzyme activity in vivo. These data suggest that the L. infantum cysteine proteinase undergoes NO-mediated S-nitrosylation, thereby representing a possible mechanism of antiparasitic host defence.

Epidemiological surveillance of leishmaniasis in HIV-1-infected individuals in Italy.

OBJECTIVE: To actively detect leishmaniasis in HIV-1-infected individuals in Italy, to describe the epidemiological features of the disease in these patients, and to compare them with epidemiological features of leishmaniasis in HIV-negative patients. DESIGN: Retrospective and prospective surveillance study. PATIENTS: Italian patients with HIV-1 infection and leishmaniasis diagnosed between 1985 and 1994. RESULTS: We recorded 116 leishmaniasis cases (115 visceral leishmaniasis), of which 94 (81%) were diagnosed over the last 4 years. Seventy-eight patients (67%) fulfilled the 1993 Centers for Disease Control and Prevention AIDS criteria. Leishmaniasis was passively reported in only 18% of cases. Leishmania incidence estimated among approximately 2700 AIDS patients living in leishmaniasis endemic areas averaged 1.6%, with a maximum of 4.9% in Sicily. These rates were up to 500-fold higher than among HIV-negative individuals living in the same areas, and were similar to those of ubiquitous opportunistic agents indicative of AIDS condition. Data from two major endemic regions indicated that overlap of HIV-1 and Leishmania infections has focal characteristics. The occurrence of small case clusters would suggest occasional modes of Leishmania transmission different from the insect vector. The isoenzyme characterization of 38 Leishmania stocks showed a zymodeme spectrum qualitatively and quantitatively different from that of the parasitic agent of visceral leishmaniasis in HIV-negative adults. CONCLUSIONS: Active surveillance provided reliable evaluation on the occurrence of HIV-Leishmania coinfections in Italy, although it was limited to hospital-based cases in this study due to general under-reporting of cases. Biological and epidemiological spectrum of the disease suggests that visceral leishmaniasis should be included among AIDS-defining pathologies.

Gastric localization of Leishmania in a patient with acquired immunodeficiency syndrome. A case report.

We report a case of gastric localization of Leishmania in a 29-year old man affected by AIDS. Gastric biopsies revealed macrophages infected with intracytoplasmic organisms attributable to Leishmania amastigotes. The authors emphasize the importance of performing random biopsies in the absence of endoscopic abnormalities.

Epidemiologic surveillance of visceral leishmaniasis in Sicily, Italy.

Visceral leishmaniasis (VL) is endemic in Sicily. Although it is a notifiable disease, there is evidence that the actual number of cases is higher than that reported. In 1987, a regional reference center for active surveillance of VL was established and it recorded a total of 284 cases through 1995, a mean of 31.5 cases/year and about four-fold more than previously reported. Of the 284 cases, 150 (53%) were children (< or = 14 years of age), and of the 134 adults, 39 (29%) were coinfected with human immunodeficiency virus (HIV). The commonest viscerotropic zymodeme of Leishmania infantum, MON 1, was identified in 40 (93%) of 43 HIV-negative and eight (57%) of 14 HIV-positive patients. Among 280 patients evaluated (i.e., all HIV-negative and 35 of 39 HIV-positive subjects), 254 (91%) were treated with meglumine antimoniate alone or in combination with other drugs; 23 (8%) received allopurinol or amphotericin B, either conventional or in liposomal form; and three terminally ill patients were not treated. Among the 245 HIV-negative patients, 236 (96%) were successfully cured, while nine (4%) (seven adults) died during the course of antimonial treatment. None of the 35 HIV-positive patients was definitively cured, although mortality was apparently associated with other opportunistic infections.

HIV-Leishmania co-infections in Italy: serological data as an indication of the sequence of acquisition of the two infections.

Twenty-two sera from visceral leishmaniasis (VL) patients with human immunodeficiency virus (HIV) infection (50% with the acquired immune deficiency syndrome) were examined for anti-Leishmania immunoglobulin G (IgG) antibodies and compared with 35 sera from VL patients without HIV (controls). Significant titres of specific IgG were found in 81.8% of co-infections. However, while control sera showed a restricted range of anti-Leishmania IgG titres, sera from co-infection cases displayed a considerable degree of variability, both quantitative and qualitative. They were clearly divided into 2 groups: one (18 sera) showing a continuous grading from nil to mid-concentrations of specific antibodies, the other (3 sera) showing titres 30-fold higher than this range. Taking into account the major immunological abnormalities involving humoral response described in HIV patient, the 2 groups may reflect a different sequence of acquisition of the 2 infective agents; the former representing VL acquired after HIV infection, and the latter representing the contrary situation.

Diffuse necrotic hepatic lesions due to visceral leishmaniasis in AIDS.

A rare case of an AIDS patient who developed scattered necrotic involvement of the liver caused by Leishmania infantum is described. Of interest, marked splenomegaly, hypergammaglobulinemia and serum anti-Leishmania antibodies were absent and an incomplete response to therapy was observed. Diagnosis of visceral leishmaniasis (VL) was achieved by the demonstration of numerous amastigotes in both hepatocytes and macrophages on liver biopsy. Hepatic necrotic lesions, which when extensive could lead to acute hepatic failure, possibly reflect an atypical manifestation of liver involvement caused by L. infantum and depend on the immunological impairment which characterizes AIDS patients, thus preventing the formation of granulomas. Our observation confirms that VL can manifest atypical aspects in HIV-positive patients depending on the degree of the immunodeficiency. The frequency and severity of this pathology accounts for the need to list VL among AIDS-defining conditions.

Early suppression of lymphoproliferative response in dogs with natural infection by Leishmania infantum.

Dogs are the domestic reservoirs of zoonotic visceral leishmaniasis caused by Leishmania infantum. Early detection of canine infections evolving to clinically patent disease may be important to leishmaniasis control. In this study we firstly investigated the peripheral blood mononuclear cell (PBMC) response to leishmanial antigens and to polyclonal activators concanavalin A, phytohemagglutinin and pokeweed mitogen, of mixed-breed dogs with natural L. infantum infection, either in presymptomatic or in patent disease condition, compared to healthy animals. Leishmania antigens did not induce a clear proliferative response in any of the animals examined. Furthermore, mitogen-induced lymphocyte proliferation was found strongly reduced not only in symptomatic, but also in presymptomatic dogs suggesting that the cell-mediated immunity is suppressed in progressive canine leishmaniasis. To test this finding, naive Beagle dogs were exposed to natural L. infantum infection in a highly endemic area of southern Italy. Two to 10 months after exposure all dogs were found to be infected by Leishmania, and on month 2 of exposure they all showed a significant reduction in PBMC activation by mitogens. Our results indicate that suppression of the lymphoproliferative response is a common occurrence in dogs already at the beginning of an established leishmanial infection.

Evaluation of the Leishmania recombinant K39 antigen as a diagnostic marker for canine leishmaniasis and validation of a standardized enzyme-linked immunosorbent assay.

Canine infections with Leishmania infantum are important as a cause of serious disease in the dog and as a reservoir for human visceral leishmaniasis (VL). Accurate diagnosis of canine infections is essential to the veterinary community and for VL surveillance programs. A standardized ELISA using a purified recombinant antigen (rK39) specific to VL was compared to the immunofluorescent antibody test (IFAT) as the standard. The ELISA was developed, optimized and evaluated using sera from 6368 dogs. The standardized ELISA and IFAT results were highly concordant. The timing and pattern of ELISA and IFAT seroconversion in dogs followed prospectively after natural infections were very similar. Antibodies reacting with rK39 were more common in asymptomatic canine infections than reported for subclinical human VL. The rK39 ELISA is a relatively simple and rapid assay for assessing the infection status of dogs, and is an alternative to IFAT, especially when screening large numbers of samples.

[Change in human visceral leishmaniasis treatment in Italy: retrospective study of 630 patients]. / Cambiamento nella terapia della leishmaniosi viscerale umana in Italia: studio retrospettivo su 630 pazienti.

Since the 1940s meglumine antimoniate (MA) has been the only first-line drug for visceral leishmaniasis (VL) treatment in Italy. From 1991 through 1994, several patients of all ages, representing 1/3 of all immunocompetent VL patients reported during that period, were enrolled in clinical trials of liposomal amphotericin B (L-AmB), which led to a novel, safe, short course of VL treatment as an alternative to MA. In the same period, other lipid-associated AmB drugs were registered in Italy for the treatment of fungal infections, i.e., AmB colloidal dispersion (ABCD) and AmB lipid complex (ABLC). A retrospective analysis was performed on data collected at the Unit of Protozoology of Istituto Superiore di Sanità, Rome, to assess whether changes have occurred in first-line drug regimens adopted in Italy for routine VL treatment, during the 1995-2002 period. The sample consisted of immunocompetent individuals clinically suspected for VL, in whom the disease was confirmed by the examination of serum and bone marrow specimens sent to the Unit by hospitals from throughout the country. Relevant information on patients was then recorded, which included drug regimens used and post-therapy results. We recorded treatment information for 630 patients, representing a large proportion (55.5%) of 1,135 immunocompetent individuals with VL reported in Italy from 1995 through 2002. About half were children (306). Every year, patients were referred by 19 to 42 hospitals, with a range of 1 to 30 patients per hospital. MA was the first-line drug used in 159 patients (25.2%). However, the proportion of MA-treated patients has steadily decreased from 55.9% in 1995 to 1.0% in 2002. We recorded the failure of MA therapy in 16 patients (10.1%), who were successfully retreated with a L-AmB regimen. The rate of MA failures significantly increased in recent years, from 5.3% in 1995 to 36.4% in 2000 (p = 0.01). AmB drugs have been the only alternative drugs used in the remaining 471 patients (74.8%). L-AmB accounted for most regimens (441, 93.6%). The proportion of patients treated with any AmB-based drugs increased from 44.1% in 1995 to 99.0% in 2002. Drug treatment was unsuccessful in 15 patients (3.2%), who were successfully retreated with a high-dose L-AmB regimen. This rate was significantly lower than the MA failure rate (p = 0.001). Results have shown a countrywide change in therapy over the period considered. A traditionally effective, but moderately toxic drug (MA) has been almost fully replaced by a new compound (L-AmB) with negligible toxicity, in an epidemiologic context of disease reemergence. Furthermore, short courses of 6 to 7 days, as required for lipid-associated AmB, are highly cost-effective if compared with 21- to 28-day courses needed for standard MA treatment.

[Infantile visceral leishmaniasis in the Campania region, Italy: experience from a Paediatric Referral Centre]. / Leishmaniosi viscerale infantile in Campania: l'esperienza del Centro Pediatrico di Riferimento.

In the first half of the 20th century, visceral leishmaniasis (VL) was a common infantile syndrome in coastal territories of the Campania region of Italy. After World War II, the incidence dropped to a few cases/year for three decades; in late 1980s the disease reemerged among both children and adults. To face the VL recrudescence, a Paediatric Reference Centre was established at the Santobono-Pausilipon hospital in Naples, for the clinical diagnosis, care and drug treatment of all infantile VL cases occurred in the Campania region. Rapid laboratory diagnosis was secured by a Diagnostic Reference Centre established at the Istituto Superiore di Sanità. Here, we report on the epidemiological and parasitological features of all cases referred to the Centre in the past 15 years. From 1990 to March 2004, a total of 255 cases were diagnosed and treated at the Centre. The Figure shows the yearly trend of patients (min. 3 cases in 1990 and 1991, max. 30 cases in 2000). There were 135 males (52.9%); the age ranged 4 months-14 years, but 189 patients (74.1%) were < or = 3 years old. The majority of the patients (189, 74.1%) were from the Naples province, with a cluster of 102 cases (40% of total patients) from the towns and districts surrounding Vesuvius. Twenty-seven cases (10.6%) were from the town of Maddaloni, Caserta province, whereas 15 cases (5.9%) were from coastal villages of the Salerno province. Only 1 and 2 cases were from Benevento and Avellino provinces, respectively. All patients but seven, who have been treated with antimonial drugs in the 1990-1993 period, were successfully treated with a liposomal amphotericin B regimen. From bone-marrow aspirate samples, 138 Leishmania cultures were obtained in EMTM and Sloppy Evans' media, of which 134 have been typed by the electrophoretic analysis of 13 isoenzymes. Two zymodemes (Z) of L. infantum were routinely identified over the study period, ZMON-1 (the commonest zymodeme in the Mediterranean area) and ZMON-72, variant from MON-1 in PGM mobility and detected only in our region. The latter, identified in 61 patients (45.5%), was found exclusively distributed in towns of the Vesuvius area and in Maddaloni until 1996, but in recent years it appears to have spread to other areas of the Naples (including the island of Ischia) and Caserta provinces, but not to Salerno province. In conclusion, the VL macrofocus of the Naples-Caserta area is probably responsible for the highest number of infantile cases among any VL macrofoci described in southern Europe. Considering the limited efforts paid to control the canine reservoir, rapid diagnosis and appropriate treatment of patients still remain the first-line control measures aimed at reducing the health impact of the disease.

A retrospective clinical study of canine leishmaniasis in 150 dogs naturally infected by Leishmania infantum.

The clinical and laboratory findings observed in 150 dogs naturally infected by Leishmania infantum, from a large endemic area of southern Italy, are described. There was a gradual onset of clinical signs and the course of the disease was progressive in almost all the cases. The majority of the dogs were mongrels (43.3 per cent), male (64.7 per cent), of medium size (50.6 per cent), three to seven years old (64.7 per cent), and living outdoors (60 per cent). They showed generalised (56.7 per cent) or symmetrical (32 per cent) lymphadenomegaly; the mucous membranes of 87 of the dogs (58 per cent) were pale and moderate or severe splenomegaly was diagnosed in 80 dogs (53.3 per cent); weight loss was observed in 32 per cent of the animals. Skin abnormalities were very common, and included dry exfoliative dermatitis (56 per cent), ulcers (40 per cent) periorbital alopecia ('lunettes') (18 per cent), diffuse alopecia (14 per cent) and onychogryphosis (24 per cent). Ocular signs were observed in 24 dogs (16 per cent) including 16 cases of keratoconjunctivitis (three with keratoconjunctivitis sicca), six cases of moderate uveitis and two cases of panophthalmitis. The acute form of the disease was diagnosed in only six dogs and was characterised by fever and generalised lymphadenomegaly, and by the absence of skin lesions. Another six dogs had severe renal failure without systemic clinical signs of leishmaniasis. The most important laboratory findings were a severe or moderate increase in gammaglobulins, hypoalbuminaemia, hyperproteinemia and anaemia. Cultures or cytology tests for L infantum parasites were positive in 134 of the dogs. Following the standard procedures developed for human lymph node and bone marrow cytology tests, the leishmania density in the dogs varied from 1+ to 2+. Leishmania antibody titres were high (> 1:160) in almost all the dogs. Immunological tests for autoantibodies were positive in 25 of 53 dogs tested in the antinuclear antibody (ANA) test, in 15 of 43 dogs tested in the latex test and in five of 24 dogs tested in the Coombs test.

Temporal trends in canine leishmaniosis in the Balearic Islands (Spain): a veterinary questionnaire. Prospective canine leishmaniosis survey and entomological studies conducted on the Island of Minorca, 20 years after first data were obtained.

Leishmaniosis is present in the Mediterranean region of Europe, where Leishmania infantum is responsible for the disease, dogs are the main reservoir, and sand flies of the Phlebotomus genus, subgenus Larroussius, are proven vectors. Some areas, including Minorca in the Balearic Islands, are considered free of the disease, despite the presence of vectors. However, in the context of the current expansion of canine leishmaniosis in parts of Europe, an epidemiological study using a veterinary questionnaire was carried out to establish the current situation of the disease in the Balearic Islands. While 50% of veterinarians thought that the incidence of canine leishmaniosis had not changed over time, 26.2% perceived an increasing trend, mainly those from Minorca, where most of the veterinarians polled (88.1%) considered the new diagnosed cases as autochthonous. A cross-sectional serological study performed in this island gave a seroprevalence rate of 24%. Seroprevalence among animals of local origin and with no history of movements to endemic areas was 31%. The presence of autochthonous canine leishmaniosis in Minorca was not correlated with an increase in vector density. The environmental and climatic factors that influenced the distribution and density of Phlebotomus perniciosus on the island and the possible causes of the apparent emergence of canine leishmaniosis in Minorca are discussed.

Clinical features of cardio-renal syndrome in a cohort of consecutive patients admitted to an internal medicine ward.

INTRODUCTION: Cardiorenal syndrome (CRS) is a disorder of the heart and kidney whereby interactions between the 2 organs can occur. We recorded the clinical features of CRS in patients consecutively admitted to an Internal Medicine ward. PATIENTS AND METHODS: We retrospectively analyzed the anthropometric, history, clinical, biochemical and treatment characteristics in 438 out of 2,998 subjects (14.6%) admitted to our unit (from June 2007 to December 2009), diagnosed with CRS, according to Acute Dialysis Quality Initiative (ADQI) recommendations. Estimated glomerular filtration (eGFR) was calculated using several equations: MDRD (Modification of Diet in Renal Disease; 2 variations GFR(MDRD186), GFR(MDRD175)), Mayo, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Cockroft-Gault. RESULTS: Mean age was 80±8 years, 222 (50.6%) were males, 321 (73.2%) were smokers, 229 (52.2%) were diabetic, 207 (47.2%) had a history of acute myocardial infarction, 167 (38.1%) had angina, 135 (30.8%) were affected by cerebrovascular disease, 339 (77.3%) had peripheral arterial disease. CRS was type 1 in 211 cases (48.2%), type 2 in 96 (21.9%), type 3 in 88 (20.1%), type 4 in 29 (6.6%) and type 5 in 14 (3.2%). eGFR, calculated by different formulae, ranged between 31 and 36 ml/min/1.73 m(2). GFR was lower in CRS type 3 than in the other types, and the values ranged between 24 and 27 ml/min/1.73 m(2). Mean hospital length-of-stay (LOS) was 9.8±6.3 days. Diuretics were the most prescribed medication (78.7%); only 5 patients underwent haemodialysis. CONCLUSIONS: CRS is common, especially in the elderly. CRS Type 1 was the prevalent subset and patients had stage 3-4 renal insufficiency. Results obtained from the GFR equations were similar although the Mayo equation tended to overestimate the eGFR.

Randomized, double-blind comparison of effects of abiciximab bolus only vs. on-label regimen on ex vivo inhibition of platelet aggregation in responders to clopidogrel undergoing coronary stenting.

BACKGROUND: On top of aspirin, an abciximab bolus-only regimen results in a 30% drop in platelet inhibition at 6 h as compared with the on-label regimen. The concomitant administration of high loading dose clopidogrel, by bridging with abciximab bolus, may sustain suppression of platelet activity over time. OBJECTIVES: To investigate the non-inferiority of abciximab bolus-only and concomitant high loading dose clopidogrel vs. abciximab bolus + infusion with respect to the inhibition of platelet aggregation (IPA) as determined by light transmission aggregometry. PATIENTS/METHODS: Seventy-three patients with non-ST segment elevation acute coronary syndromes underwent double-blind randomization to abciximab bolus followed by a 12-h placebo infusion and concomitant 600-mg clopidogrel vs. abciximab bolus + a 12-h infusion and 300 mg of clopidogrel. IPA was determined by light transmission aggregometry throughout 24 h. Clopidogrel poor responsiveness was defined as ≥ 50% 5 µmol L⁻¹ ADP-induced maximum platelet aggregation. RESULTS: In clopidogrel responders (n = 68), IPA after 20 µmol L⁻¹ ADP at 4 h was 89% ± 13% in the bolus-only arm vs. 92% ± 14% in the bolus + infusion arm (P = 0.011 for non-inferiority). IPA after 5 or 20 µmol L⁻¹ ADP and 5 or 15 µmol L⁻¹ TRAP and the proportion of patients showing ≥ 80% IPA did not differ at any time point, irrespective of clopidogrel responsiveness status. Thirty-day outcomes were similar, whereas hemoglobin (0.91 ± 0.8 vs. 0.5 ± 0.7 g dL⁻¹ ; P = 0.01) and platelet count mean drop (41.7 ± 57 vs. 18.6 ± 34 109 L⁻¹; P = 0.042) were significantly reduced in the bolus-only arm. CONCLUSIONS: Withholding abciximab post-bolus infusion in patients receiving high loading dose clopidogrel does not impair platelet inhibition throughout 24 h, and has the potential to improve the safety profile of the drug at reduced costs.