Prevalence of Cryptococcal Antigen and Outcomes in People With Human Immunodeficiency Virus in Honduras: A Cohort Study

Background

Cryptococcal meningitis is a major cause of death among people with human immunodeficiency virus (PWH). Cryptococcal antigen (CrAg) testing of asymptomatic patients is an important public health measure to reduce mortality in high-incidence areas. However, limited data exist on CrAg prevalence in Central America.

Methods

We conducted a prospective cohort study at the 2 largest human immunodeficiency virus (HIV) clinics and hospitals in Honduras. Cryptococcal antigen in serum and cerebrospinal fluid was performed in individuals with HIV who had CD4 ≤100 cells/mm³ between 2017 and 2018. After CrAg testing, individuals were observed for 12 months to assess mortality using adjusted Cox proportional hazard models.

Results

A total of 220 PWH were tested for CrAg, 12.7% (n = 28) of which tested positive. Cryptococcal antigen prevalence was higher among hospitalized individuals in 40% (n = 10 of 25) of the cases. The proportion (35.8%) of individuals taking antiretroviral therapy was significantly (P < .01) lower among those who tested positive for CrAg. Overall mortality among the cohort was 11.4% (n = 25 of 220) by 12 months. Cryptococcal antigen-positive cases were at a significantly higher risk of death (adjusted hazard ratio, 2.69; 95% confidence interval, 1.07-6.84) compared with CrAg-negative participants.

Conclusions

Cryptococcal antigen prevalence in Honduras was high among PWH. Moreover, individuals who tested positive for CrAg testing were at a higher risk of death. Systemic CrAg of PWH with a CD4 ≤100 cells/mm³ should be routinely performed in Central America.

Piperine, active substance of black pepper, alleviates hypertension induced by NO synthase inhibition

OBJECTIVES

The presented study is aimed on exploring the effects of black pepper on blood pressure in the rat model of experimental hypertension induced by chronic NO synthesis inhibition.

BACKGROUND

Piperine, the compound of black pepper, can cause a significant decrease of blood pressure in normotensive rats possibly via calcium channel blockade, a pathway that is known to be effective in prevention of L-NAME (N(G)-nitro-L-arginine methyl ester) induced hypertension.

METHODS

Wistar rats were administered clear water (C), L-NAME (40 mg/kg/day, L), piperine (20 mg/kg/day) in corn oil by oral gavage with L-NAME (LP) or without it (P) for 6 weeks. The systolic blood pressure was measured weekly. Specimens of thoracic aorta were processed in paraffin and histological slices were stained with hematoxylin and eosin, Mallory's phosphotungstic acid hematoxylin (PTAH), orcein, antibodies against inducible NO synthase (iNOS) and smooth muscle cells actin (SMCA). Microscopic pictures were digitally processed and morphometrically evaluated.

RESULTS

L-NAME increased the blood pressure, cross-sectional area of aorta, media thickness, elastin and SMCA synthesis and PTAH positive myofibrils relative and absolute content in the aortic media, wheras it decreased percentual content of iNOS, elastin and SMCA. Piperine decreased the blood pressure rise from the third week of treatment, synthesis of elastin and the percentual and absolute content of PTAH positive myofibrils, however, it did not affect other parameters.

CONCLUSION

Oral administration of piperine is able to partially prevent the increase of blood pressure caused by chronic L-NAME administration. This effect is probably caused by the blockage of voltage-dependent calcium channels and supported by filamentous actin disassembly (Tab. 1, Fig. 2, Ref. 35).