Recurrent Staphylococcus aureus renal abscess in a child positive for the human immunodeficiency virus

Efficacy of Novel Antistaphylococcal Ectolysin P128 in a Rat Model of Methicillin-Resistant Staphylococcus aureus Bacteremia

Staphylococcus aureus causes systemic infections with high morbidity and mortality, and the emergence of drug-resistant strains is a rapidly growing clinical concern. Novel therapeutic agents are required to tackle S. aureus infections. P128 is a bacteriophage-derived chimeric ectolysin with potent and rapid bactericidal activity against S. aureus In the present study, the efficacy of P128 was evaluated in a newly developed rat model of S. aureus bacteremia. Prior to in vivo testing, P128 was shown to be stable in whole blood by incubation in rat blood for up to 6 h and testing its bactericidal activity against the methicillin-resistant S. aureus isolate USA300. Rats succumbed to intravenous challenge with 10⁹ CFU of S. aureus USA300, resulting in 80 to 100% mortality by day 14. Evaluation of the bacterial load in various organs at 96 h postinfection revealed high bacterial counts in the kidney, and this correlated with the presence of renal abscesses. Treatment of infected animals with P128 either by intravenous bolus administration via tail vein or by 1-h infusion via the jugular vein at 2 h postinfection resulted in the dose-dependent survival of rats. P128 treatment also resulted in very few or no abscesses in the kidneys. These data show that P128 is stable in the physiological milieu and that intravenous treatment with P128 is highly effective in rescuing rats from S. aureus bacteremia. P128 can be a novel therapeutic option for treatment of S. aureus systemic infections.

Urologic aspects of HIV infection

Although lifespan has dramatically improved in the human immunodeficiency virus-positive (HIV+) population, HIV and its treatment continue to be a source of substantial morbidity in many organ systems, including the genitourinary tract. As the number of long-term survivors increases with advances in antiretroviral therapy, age-associated urologic symptoms are also becoming increasingly relevant considerations for people living with HIV. Primary care physicians have a major role to play in maintaining the genitourinary health of their HIV+ patients. This role is of great importance not just for the well-being of the individual patient but for the public health, as the genitourinary tract is a common vector for HIV transmission. In this article the authors review the management of the genitourinary system in patients with HIV infection. Particular consideration is given to urinary tract infections, lower urinary tract symptoms, renal insufficiency, sexual and fertility problems, and cancers of the genitourinary tract. Management algorithms are outlined and indications for referral to a urologist are emphasized.

The urological management of the patient with acquired immunodeficiency syndrome

In people infected with the human immunodeficiency virus (HIV) both the CD4 T-cell count and the viral load are used to monitor disease progression to acquired immunodeficiency syndrome (AIDS). CD4 counts of <500/mm(3) are associated with opportunistic infections and certain malignancies, so-called 'AIDS-defining' conditions. Highly active antiretroviral therapy, using combinations of reverse transcriptase inhibitors and/or protease inhibitors, can improve considerably the prognosis of people who are HIV-positive, but such therapy is not yet widely available in many developing countries. People with AIDS are predisposed to urinary tract infection (UTI) by uncommon bacteria and pathogens, e.g. fungi, parasites and viruses, which may affect any urogenital organ; treatment should be culture-specific and long-term, because there is a tendency to recurrence, infection with multiple organisms and resistant isolates. Voiding dysfunction in patients with AIDS is usually a result of neurological complications caused by opportunistic infections, and has a poor prognosis. Of patients with AIDS, 30-50% develop a cancer, especially Kaposi's sarcoma (KS) and non-Hodgkin's lymphoma (NHL). KS may involve any urogenital organ, but is usually part of systemic disease. Small lesions on the external genitalia can be treated with laser, cryotherapy or surgical excision, larger lesions with radiotherapy, and disseminated or visceral KS with multidrug chemotherapy. NHL may involve the kidneys, testes and retroperitoneal lymph nodes, thus obstructing the ureters, which may require ureteric stenting or percutaneous nephrostomy. NHL can be treated with radiotherapy and combination chemotherapy. Urolithiasis in patients with AIDS may be caused by indinavir, a protease inhibitor, but the more common types of stones may also occur. Fluid-electrolyte and acid-base disturbances are common in patients with advanced AIDS, secondary to vomiting, diarrhoea, malnutrition or septicaemia. HIV-associated nephropathy occurs in 10-30% of patients, and often leads to renal failure. Testicular atrophy is common, leading to infertility, erectile dysfunction (ED) and decreased libido. Treatment for ED must include counselling about strategies to reduce the transmission of HIV. The risk of HIV transmission after parenteral exposure to blood from an HIV-positive patient is relatively low (0.2-0.4%); the urologist can reduce the risk of transmission during surgery by adopting certain precautions. After occupational exposure to HIV, chemoprophylaxis with antiretroviral medication can significantly reduce the probability of HIV transmission.

Perinephric and renal abscesses in children: a study of three cases

Perinephric and renal abscesses are rare in childhood, but they must be remembered in the differential diagnosis of fever and abdominal or flank pain. This paper reports three cases whose solution was found after clinical and surgical treatment. The importance of ultrasound and computerized tomography (CT) in prompt diagnosis is highlighted in this work. The use of these methods along the improved antimicrobial therapy may result in decrease in mortality due to this pathology.