Early syphilis in a man with a negative Treponema pallidum enzyme immunoassay-IgM.

Most serological tests for syphilis rely on an individual's ability to produce antibodies. A single screening test may be unreliable for screening in those with primary immunodeficiency. We present the first reported case of primary and secondary syphilis with negative Treponema pallidum enzyme immunoassay-IgM and Venereal Disease Research Laboratory tests in a man with common variable immunodeficiency.

Implanon® failure in an HIV-positive woman on antiretroviral therapy resulting in two ectopic pregnancies.

Since its introduction in 1999, Implanon® remains one of the preferred contraceptive choices for many women as it offers a highly effective means of long-term contraception for three years that does not rely on adherence. Like all hormonal contraceptives, certain hepatic enzyme-inducing drugs may reduce its efficacy. We present an interesting case of an HIV-positive woman on antiretroviral therapy having tubal pregnancies on two separate occasions with Implanon in place.

Plasma inhibitory activity against tumour necrosis factor in fulminant hepatic failure.

1. Soluble tumour necrosis factor receptors released into the circulation inhibit the effects of excess tumour necrosis factor-alpha and represent an important protective response. 2. In this study we have measured the levels of tumour necrosis factor and soluble tumour necrosis factor receptors p55 and p75 in the plasma of 10 patients with fulminant hepatic failure and 10 healthy control subjects. The capacity of the plasmas at varying dilutions to inhibit the biological activity of 1000 pg/ml of recombinant tumour necrosis factor in a tumour necrosis factor cytotoxicity assay in vitro was also determined. 3. The mean plasma levels of tumour necrosis factor in patients with fulminant hepatic failure (48.4 +/- 10.9 pg/ml) were significantly increased compared with normal control subjects (6.1 +/- 1.04 pg/ml, P < 0.01). Plasma soluble tumour necrosis factor receptors p55 and p75 were also significantly elevated in patients with fulminant hepatic failure (18.16 +/- 9.94 ng/ml and 16.06 +/- 9.93 ng/ml respectively) when compared with normal control subjects (1.28 +/- 0.24 ng/ml and 1.62 +/- 0.91 ng/ml, P < 0.001). 4. Fulminant hepatic failure plasma had a much lower capacity to inhibit tumour necrosis factor bioactivity in vitro, with a statistically significant difference between the inhibitory capacity of the fulminant hepatic failure and normal plasma seen at plasma dilutions of 1:5 and 1:20 (P < 0.05). 5. The reduced tumour necrosis factor neutralization capacity observed in fulminant hepatic failure, despite the increased levels of soluble tumour necrosis factor receptors, suggests enhanced susceptibility to the potential deleterious effects of tumour necrosis factor in fulminant hepatic failure.

Clearance and tissue distribution of staphylococcal enterotoxin A in the rat and potential use of adsorbents for removal from plasma.

Many of the profound effects of staphylococcal septicaemia are thought to be the result of entry of enterotoxins into the systemic circulation. The aim of this study was to investigate the disposition of staphylococcal enterotoxin A (SEA) in the rat and its possible removal from blood. SEA labelled with 125I was administered intravenously (250 micrograms/kg) to rats. The blood clearance of SEA showed a biphasic pattern; an initial fast disappearance (half-life c. 3 min) was followed by a slower one (half-life c. 2 h). Thirty minutes after injection of 125I-labelled SEA, most of the radioactivity was concentrated in the kidneys, indicating that renal excretion was the main route of elimination of SEA. The adsorption capacities of polymer-coated activated charcoal (DHP-1 and Adsorba 150C), uncharged resin (Amberlite XAD-7), anion exchange resin (Dowex-1) and polymyxin B matrix were assessed by measurement of the equilibrium adsorption isotherms for SEA. DHP-1 charcoal, Amberlite XAD-7 resin and Dowex-1 resin adsorbed similar amounts of SEA in human plasma. Plasma perfusion experiments were performed in vitro with small columns containing either charcoal or resin adsorbents. Over 4 h perfusion, DHP-1 charcoal removed 50% of the initial amount of 125I-SEA, Adsorba 150C charcoal 8.1% of SEA and Amberlite XAD-7 resin 32.5% of SEA. These results suggest that it may be feasible to develop the adsorbent columns for direct removal of SEA from the plasma of patients with staphylococcal septicaemia.

In vitro plasma perfusion through adsorbents and plasma ultrafiltration to remove endotoxin and cytokines.

In vitro plasma perfusion experiments were performed using small columns containing either resin or charcoal adsorbents to assess the removal of cytokines and endotoxin. 125I-labelled tumor necrosis factor-alpha (TNF-alpha; 500 pg/ml) and interleukin-6 (IL-6; 10 ng/ml) were added individually to human plasma. Over 4 hr of perfusion, Amberlite XAD-7 resin removed 32.5% +/- 3.3% (n = 5) of the initial amount of TNF-alpha and 71.4% +/- 3.8% (n = 5) of the initial amount of IL-6. DHP-1 polyhema-coated activated charcoal removed 17.2% +/- 6.2% (n = 5) of TNF-alpha and 48.5% +/- 7.4% (n = 5) of IL-6. Preliminary experiments were performed with lipopolysaccharide (LPS; 100 ng/ml) and interleukin-1 alpha (IL-1 alpha; 500 pg/ml), which showed that, over 4 hr, Amberlite XAD-7 removed 10.3% of the initial LPS and 29.1% of IL-1 alpha, whereas DHP-1 charcoal removed 23.2% of the initial LPS and 65.3% of IL-1 alpha. In vitro plasma ultrafiltration with either polysulfone or polyacrylonitrile membranes, as used clinically in haemodialysis, was performed with recirculation of plasma containing LPS or TNF-alpha. Neither of the substances was filtered to a significant degree. In conclusion, direct removal of these inflammatory mediators from the circulation of patients with multiorgan failure due to fulminant hepatic failure or sepsis would be possible by perfusion of plasma through adsorbents but not by haemodialysis.