Prevalence of Antiretroviral Drug Resistance in Patients Who Are Not Responding to Protease Inhibitor-Based Treatment: Results From the First National Survey in South Africa

Limited data exist on human immunodeficiency virus type 1 (HIV-1) resistance in patients who are not responding to protease inhibitor (PI)-based regimens in resource-limited settings. This study assessed resistance profiles in adults across South Africa who were not responding to PI-based regimens. pol sequencing was undertaken and submitted to the Stanford HIV Drug Resistance Database. At least 1 major PI mutation was detected in 16.4% of 350 participants. A total of 53.4% showed intermediate resistance to darunavir/ritonavir, whereas high-level resistance was not observed. Only 5.2% and 32.8% of participants showed high-level and intermediate resistance to etravirine, respectively. Although the prevalence of major PI mutations was within previously reported ranges, most patients will likely experience virological suppression during receipt of currently available South African third-line regimens.

HIV-1 antiretroviral drug resistance patterns in patients failing NNRTI-based treatment: results from a national survey in South Africa

BACKGROUND

Routine HIV-1 antiretroviral drug resistance testing for patients failing NNRTI-based regimens is not recommended in resource-limited settings. Therefore, surveys are required to monitor resistance profiles in patients failing ART.

METHODS

A cross-sectional survey was conducted amongst patients failing NNRTI-based regimens in the public sector throughout South Africa. Virological failure was defined as two consecutive HIV-1 viral load results >1000 RNA copies/mL. Pol sequences were obtained using RT-PCR and Sanger sequencing and submitted to Stanford HIVdb v7.0.1.

RESULTS

A total of 788 sequences were available for analysis. Most patients failed a tenofovir-based NRTI backbone (74.4%) in combination with efavirenz (82.1%) after median treatment duration of 36 months. K103N (48.9%) and V106M (34.9%) were the most common NNRTI mutations. Only one-third of patients retained full susceptibility to second-generation NNRTIs such as etravirine (36.5%) and rilpivirine (27.3%). After M184V/I (82.7%), K65R was the most common NRTI mutation (45.8%). The prevalence of K65R increased to 57.5% in patients failing a tenofovir regimen without prior stavudine exposure. Cross-resistance to NRTIs was often observed, but did not seem to affect the predicted activity of zidovudine as 82.9% of patients remained fully susceptible to this drug.

CONCLUSIONS

The introduction of tenofovir-based first-line regimens has dramatically increased the prevalence of K65R mutations in the HIV-1-infected South African population. However, most patients failing tenofovir-based regimens remained fully susceptible to zidovudine. Based on these data, there is currently no need to change either the recommended first- or second-line ART regimens in South Africa.

High incidence of latent tuberculous infection among South African health workers: an urgent call for action

SETTING

In South Africa, health care workers (HCWs) are at two-fold greater risk of acquiring tuberculosis (TB) disease than the general population. Few studies have evaluated the risk of incident tuberculous infection.

OBJECTIVE

To determine the incidence and risk factors for latent tuberculous infection (LTBI) among HCWs and to compare the results of the interferon-gamma release assay (IGRA) with those of the tuberculin skin test (TST).

DESIGN

HCWs, including medical students, underwent a TST and human immunodeficiency virus (HIV) and IGRA testing at baseline and 12 months, and IGRA at 6 months. The participants kept 12-month TB exposure logs.

RESULTS

Among 199 participants (150 [76%] females, median age 31 years [range 20-61]), incident LTBI was documented using IGRA in 25/97 (26%; incident rate 29 cases/100 person-years [py], 95%CI 20-44) and using TST in 25/93 (27%; incident rate 29 cases/100 py, 95%CI 19-42). Agreement between TST and IGRA was poor (44.8%, κ = 0.23). Higher annual exposure to TB cases was reported among persons with LTBI than in those who were persistently IGRA-negative (81 cases, 95%CI 61-102 vs. 50 cases, 95%CI 43-57, P < 0.01).

CONCLUSION

The high LTBI incidence and the association of incident LTBI with annual TB caseload among HCWs indicate that more effective TB infection control should be implemented in South African health care facilities.

The effect of antral acidification on serum gastrin levels in neonatal pigs

The cause of the physiologic hypochlorhydria and hypergastrinemia of the newborn is not understood. The effect of antral acidification on basal serum gastrin was studied in 32 anesthetized Landrace piglets divided into four groups of eight animals each: Group A, 1 to 7 days old; Group B, 8 to 15 days old; Group C, 16 to 24 days old; and Group D, 25 to 48 days old. After a 2-hr fast, halothane anesthesia was administered. Inflow and outflow cannulae were inserted into the gastric lumen to create an intact isolated gastric antrum. HCl in saline (pH 2.5) was infused (10 cc/min) for 15 min and drained by continuous suction. The effluent was confirmed to be pH 2.5. Portal venous blood samples were obtained at basal levels and at 5, 10, and 15 min and assayed for gastrin. All groups had markedly elevated serum gastrin levels, as compared to normal adult values, in the basal state. Basal gastrin levels declined with increasing age to approach adult values by 7 weeks. Following antral acidification in Groups A, B, and C, there was a significant reduction in serum gastrin. All suppressed values remained significantly higher than adult basal, however. There was no significant change in gastrin levels in Group D with acidification.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular trauma of the extremities: factors causing failure of arterial repair

Vascular trauma of the extremities is a significant problem in our society as a result of vehicle accidents and violence. Excellent results of vascular repair can be expected with strict attention to bypass of all damaged vessel, proximal and distal embolectomy, regional heparinization, liberal fasciotomy, fixation of associated fractures, and soft tissue coverage of the repaired vessel.

Pediatric trauma associated with all-terrain vehicles

The frequency of injuries secondary to use of all-terrain vehicles (ATV) is increasing at an alarming rate, and these injuries are usually multiple and severe. Between January 1, 1983, and February 28, 1985, 415 pediatric patients were admitted to the University of Virginia Hospital for care of injuries secondary to trauma; 66 of these patients required intensive care. Of the 415 patients, 12 were injured secondary to ATV use, and four of these required intensive care. The average age was 12 years (range 2 to 16 years), and the average hospital stay was 20 days. Injuries included five closed head injuries, two associated with a basilar skull fracture requiring intracranial pressure monitoring; five long bone fractures, two requiring open reduction and internal fixation; two small bone fractures; two splenic ruptures; two liver lacerations, one of them requiring laparotomy; and one renal hematoma. One patient has required long-term rehabilitation for neurologic deficits. Physicians and the public should be aware of the injury potential of these vehicles and should advocate legislation promoting helmet laws and high safety standards for ATV users.