Hepatic venous-portal gradient (HVPG) measurement: pearls and pitfalls

Hepatic venous pressure gradient (HVPG) is the gold-standard for measurement of portal hypertension, a common cause for life-threatening conditions such as variceal bleeding and hepatic encephalopathy. HVPG also plays a crucial role in risk stratification, treatment selection and assessment of treatment response. Thus recognition of common pitfalls and unusual hepatic venous conditions is crucial. This article aims to provide a radiographical and clinical guide to HVPG with representative clinical cases.     

Controversies in transfusion medicine. Alanine aminotransferase screening of blood donors: pro

In my opinion, independent, carefully conducted scientific studies indicate that an accurate, rapid, relatively sensitive, and inexpensive laboratory test substantially reduces the major long-term risk of blood transfusion in the United States; donor ALT has emerged as one of the most effective laboratory determinants for reducing the incidence of NANB PTH. Despite its nonspecificity and limited predictive value, ALT screening may prevent up to 30 percent of cases, one-half of which would progress to chronic liver disease and then possibly to cirrhosis and hepatocellular carcinoma. Blood donors appear to understand and accept the testing rationale as a reasonable precaution. Admittedly, ALT screening is not a perfect solution. It has not been validated by prospective studies and probably never will be. Determination of the proper cutoff value remains controversial. However, the risk of PTH progresses with increasing ALT levels, so that the real issue is not whether to test, but how best to configure the test to exclude the fewest false-positive donors while detecting the most true-positive donors. It is undesirable and expensive to discard safe units of blood, but the primary responsibility of blood collectors is to ensure an adequate supply of safe components. Some still consider the ALT assay technically too demanding for routine use. However, technical concerns regarding performance and interpretation are not insurmountable, and both quality control and proficiency testing are being addressed at the national level. The assay is capable of great precision, and a system employing a national standard and single cutoff has already been described and tested with excellent results. Circumstances have changed since donor screening with ALT was widely implemented in 1986. More thorough screening and testing have eliminated many high-risk donors. Public expectations have changed as well. While it is neither reasonable nor responsible to promise the public blood transfusions without risk, neither is it prudent to propose any major change in management of the blood supply without compelling evidence that such a change will not impair transfusion safety. It is hard to defend discontinuing the ALT screen at this time, especially when the costs of retaining it are minimal and the benefits clearly greater than those of screening for HTLV-I and for Treponema pallidum (in the United States) or HIV-2 (in West Germany). A first-generation assay specific for antibody to hepatitis C will probably be available within a year.(ABSTRACT TRUNCATED AT 400 WORDS)     

Plague. A clinical review of 27 cases.

We reviewed the medical records of 27 patients with plague seen at the Gallup (NM) Indian Medical Center between 1965 and 1989. Nineteen patients had bubonic plague and eight had septicemic plague. Three patients with septicemic plague and three with bubonic plague died. The patients presented with five different clinical pictures. Ten patients presented with classic signs of plague, five with the appearance of an upper respiratory tract infection, five with a nonspecific febrile syndrome, four with the appearance of a gastrointestinal or urinary tract infection, and three with the appearance of meningitis. Blood cultures were positive in 24 of 25 cases, and bubo aspirate cultures were positive in 10 of 13 cases. All six patients who died were under 30 years old, and all the deaths were related to a failure to treat initially with an antibiotic appropriate for plague. Plague is a treatable disease, but clinicians must have a high index of suspicion and give appropriate antibiotics at the earliest possible time to patients whose presentation suggests plague.     

Sequential organ scoring as a measure of effectiveness of care in the high-dependency unit

High-dependency units are of benefit to patients and to the associated intensive care unit. However, the effectiveness of high-dependency care has not been quantified. We studied 100 consecutive patients whose high-dependency unit admission was longer than 48 h. The Logistic Organ Dysfunction System was used to assess organ dysfunction on a daily basis in these patients. The median Logistic Organ Dysfunction System score on admission was 3. The mean duration of stay was 4.3 days, and the median Logistic Organ Dysfunction System score on day 4 was 1. Sixty-six per cent of patients had a lower Logistic Organ Dysfunction System score at discharge. In the remaining patients, the commonest reason for no change or a higher Logistic Organ Dysfunction System score was renal dysfunction. High-dependency care is effective in the majority of patients in terms of improved physiological status and most patients were discharged with minor physiological dysfunction. This level of physiological dysfunction could be applied as a discharge threshold. Poorer patient outcome is associated with increased age and a longer stay on the unit. This poor outcome was commonly due to renal system dysfunction, and invariably followed surgery.     

Chromosomal disorders and male infertility

Infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family. Despite this, the molecular and genetic factors underlying the cause of infertility remain largely undiscovered. Nevertheless, more and more genetic factors associated with infertility are being identified. This review will focus on our current understanding of the chromosomal basis of male infertility specifically: chromosomal aneuploidy, structural and numerical karyotype abnormalities and Y chromosomal microdeletions. Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans. Aneuploidy is predominantly maternal in origin, but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts. Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm. Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed, as well as the application of preimplantation genetic diagnosis (PGD) in such cases. Clinical recommendations where possible will be made, as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.