Cardiology
In cardiology, genetic conditions such as Brugada syndrome can share features with related disorders caused by mutations in the same gene. An overlap syndrome can be seen whereby a mutation in the SCN5A gene encoding the cardiac sodium channel causes a reduction in the peak sodium current leading to the typical ECG features of Brugada syndrome, but which simultaneously increases the sustained late sodium current leading to the ECG features of Long QT syndrome type 3. Brugada syndrome can also overlap with arrhythmogenic cardiomyopathy due to certain mutations in the plakophilin gene. See also
Autoimmune
Mixed connective tissue disease

References
Further reading
The Myositis Association Overlap Syndrome 2011 Conference Presentation


== External links ==
Atovaquone, sold under the brand name Mepron, is a quinone antimicrobial medication for the prevention and treatment of Pneumocystis jirovecii pneumonia (PCP).Atovaquone is a chemical compound that belongs to the class of naphthoquinones. Atovaquone is a hydroxy-1,4-naphthoquinone, an analog of both ubiquinone and lawsone, with antipneumocystic activity. Medical uses
Atovaquone is a medication used to treat or prevent:

For pneumocystis pneumonia (PCP), it is used in mild cases, although it is not approved for treatment of severe cases. For toxoplasmosis, the medication has antiparasitic and therapeutic effects. For malaria, it is one of the two components (along with proguanil) in the drug Malarone. Malarone has fewer side effects and is more expensive than mefloquine. Resistance has been observed. For babesia, it is often used in conjunction with oral azithromycin.Trimethoprim/sulfamethoxazole (TMP-SMX, Bactrim) is generally considered first-line therapy for PCP (not to be confused with sulfadiazine and pyrimethamine, which is first line for toxoplasmosis). However, atovaquone may be used in patients who cannot tolerate, or are allergic to, sulfonamide medications such as TMP-SMX. In addition, atovaquone has the advantage of not causing myelosuppression, which is an important issue in patients who have undergone bone marrow transplantation. Atovaquone is given prophylactically to kidney transplant patients to prevent PCP in cases where Bactrim is contraindicated for the patient. Malaria
Atovaquone, as a combination preparation with proguanil, has been commercially available from GlaxoSmithKline since 2000 as Malarone for the treatment and prevention of malaria. Research
COVID-19
Preliminary research found that atovaquone could inhibit the replication of SARS-CoV-2 in vitro.