Dr. Robert Micheletti delivered an engaging lecture on trends in infectious disease during the afternoon sessions of Thursday’s SDPA Digital conference. He began his lecture reiterating the research of dermatologic manifestations of COVID-19 through illustrating case presentations and discussion of correlates to disease progression and severity. For example, Dr. Micheletti relayed Chilblain-like presentations of COVID-19 are most common in young adolescents and adults and tend to appear later in the disease course and may be the only symptom for these patients. He noted “due to limitations on testing it has been difficult to confirm” these cases as COVID positive patients. Additional presentations discussed included vesicular, morbilliform, and livedoid eruptions.
Next, Dr. Micheletti reviewed the increase of syphilis cases in the US. Cases of syphilis are increasing most in the west, south, and in large urban areas of the US with the highest incidence in patient populations that include men who have sex with men, patients of color, and patients from underserved populations who have decreased access to care. Of note, Dr. Micheletti reported that an RPR can be negative in the early weeks of primary syphilis emphasizing the need for a repeat RPR in patients for whom syphilis is of high concern. Further discussion focused on rare conditions presenting in immunosuppressed patients at increased rates including Alternaria, atypical mycobacterium, and cryptococcal presentations.
Dr. Micheletti went on to discuss climate change and the returning traveler. He reviewed the three stages of Lyme disease, utilizing case presentations. He relayed that if you see a rash that appears to be erythema migrans, you assume Lyme disease diagnosis and should initiate treatment with doxycycline. Dr. Micheletti does not recommend ordering titers for Lyme disease due to the difficulty of interpretation and misleading results. Additional tick-borne diseases discussed include Lone Star disease and Rocky Mountain spotted fever (RMSF). RMSF tends to present 1-2 weeks post tick bite with petechial lesions around the wrists and ankles. Dr. Micheletti reports RMSF is important to recognize as it is a progressive disease that if left untreated can be fatal.
Finally, further vector-borne diseases reviewed included dengue fever, Chikungunya, Zika, leishmania, and myiasis through case presentations. Dengue fever typically presents with fever, retro-orbital headache, and rash. The morbilliform rash of dengue fever will have “islands of sparing” that help clue the clinician to this diagnosis. Dr. Micheletti concluded his discussion by reiterating skin as a helpful clue, the importance of keeping an open mind in the context of a patient’s overall medical status, particularly in the immunosuppressed for whom it is important to be cautious in working up these patients.