Episode #85 of the Infectious Disease Puscast features Drs. Daniel Griffin and Sarah Dong reviewing key literature from early to mid-July 2025. The discussion covers significant developments across virology, bacteriology, mycology, and parasitology, with a strong emphasis on antimicrobial resistance and evolving clinical guidelines. Key topics include a novel "shock and kill" strategy for eliminating latent HIV reservoirs, and the alarming rise of tetracycline-resistant Neisseria gonorrhoeae, strongly linked to the increasing use of Doxy-PEP, which also impacts resistance in Staphylococcus aureus and Group A Strep. The hosts delve into major updates in clinical guidelines, including new IDSA recommendations for shorter, 5-7 day treatment courses for complicated UTIs, and a controversial new Community-Acquired Pneumonia (CAP) guideline from the American Thoracic Society, from which the IDSA withdrew due to disagreements over antibiotic stewardship. Other notable studies include the successful use of AI (Microsoft Co-pilot) for diagnosing histoplasmosis, the lack of benefit for postoperative antifungals after aspergilloma resection, and concerning evidence of Chagas disease vectors infected with T. cruzi feeding on humans in Florida.
Infectious Disease Puscast #85: A Review of Recent Literature
2:52 A "Shock and Kill" Approach to HIV: A study in JID explores a method to eliminate latent HIV reservoirs. Researchers used a cocktail of drugs, including latency reversal agents, to "wake up" the integrated provirus in infected cells, leading to their selective destruction. This is presented as a promising step towards an HIV cure by targeting the source of viral rebound.
7:34 The Rise of Resistant Gonorrhea: A New England Journal of Medicine article highlights a dramatic increase in tetracycline-resistant Neisseria gonorrhoeae (carrying the tetM gene) in the US, rising from 10% in 2020 to over 30% in 2024. This increase is linked to the widespread use of doxycycline for chlamydia and as post-exposure prophylaxis (Doxy-PEP).
10:06 Doxy-PEP's Wider Impact: A related paper in CID shows that Doxy-PEP use is also associated with increased colonization by tetracycline-resistant Staphylococcus aureus and Group A Streptococcus, raising significant concerns about broad-spectrum resistance driven by this preventative strategy. A critical worry is that some gonorrhea strains also show resistance to ceftriaxone, our last effective antibiotic.
11:59 Prophylaxis for Recurrent UTIs: A trial on methenamine hippurate for preventing recurrent UTIs in older women found it reduced the incidence of UTIs by 25% during the 6-month treatment period. However, the study noted a potential "rebound" effect, with an increased risk of relapse after the therapy was stopped.
15:51 Controversial New Pneumonia (CAP) Guidelines: The American Thoracic Society (ATS) published new guidelines for Community-Acquired Pneumonia. A point of major controversy is the recommendation to empirically treat patients with comorbidities and a positive respiratory virus test with antibiotics. The Infectious Diseases Society of America (IDSA) disagreed with this stance and formally withdrew from co-publishing the guideline due to antibiotic stewardship concerns.
21:27 New Guidelines for Complicated UTIs (cUTI): The IDSA released new practice guidelines for complicated UTIs. Key changes include simplifying the definition of cUTI (infection beyond the bladder), and recommending shorter antibiotic courses of 5-7 days for most patients, a shift from the previous standard of 10-14 days.
28:34Staph aureus in Urine as a Signal: A study examined an intervention to prompt follow-up blood cultures for patients with Staphylococcus aureus in their urine. While the alert increased testing, the yield for finding associated bacteremia was low (1-in-11 to 1-in-15), and the finding was almost exclusively relevant in male patients.
34:17Candida auris in Dialysis Centers: An MMWR report on Candida auris (recently renamed Candidozyma auris) in hemodialysis facilities found no evidence of transmission, even in centers that were unaware of a patient's colonization status and were only using standard infection control procedures.
35:57 No Benefit for Post-Op Antifungals for Aspergilloma: A randomized trial found that a 3-month course of voriconazole after surgical resection of a pulmonary aspergilloma in immunocompetent patients provided no benefit. There was no recurrence in either the treatment or control group, but the treatment group experienced adverse effects.
41:34 AI Excels at Diagnosing Histoplasmosis: A study published in PLoS Neglected Tropical Diseases tested the ability of various large language models (LLMs) to diagnose histoplasmosis from clinical vignettes. Microsoft's Co-pilot demonstrated striking performance, correctly identifying the diagnosis in over 90% of cases, far surpassing other models like ChatGPT.
44:27 Chagas Disease Vectors Found in Florida: A study revealed concerning evidence of Chagas disease vectors ("kissing bugs") in Florida. Nearly 30% of the tested bugs were infected with Trypanosoma cruzi, and blood meal analysis showed that humans accounted for a quarter of their meals, indicating significant vector-human contact and the potential for local transmission.