A 54-year-old male, diagnosed with HIV-1 infection 8 years earlier, was well controlled on Atripla (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil 245 mg) with CD4 count 370 cells/mm3 and viral load <40 copies/ml presented with fever, weight loss and shortness of breath. Chest imaging found a large left pleural effusion with left lower lobe consolidation. Fully sensitive M. tuberculosis was isolated from pleural specimens. He responded to standard anti-tuberculosis treatment (rifampicin, isoniazid, pyrazinamide and ethambutol). Atripla was continued with additional efavirenz 200 mg o.d. to overcome predicted rifampicin-efavirenz drug interaction. After 2 months, he developed marked reduction in libido with erectile dysfunction. Investigations found serum total testosterone 11 nmol/l, SHBG 170 nmol/l, calculated free testosterone 60 pmol/l, LH 14 IU/ml and FSH 15 IU/ml. Efavirenz has a direct oestrogenic effect by modulating oestrogen receptors [], and this effect may have been exacerbated by SHBG elevation (HIV infection, anti-tuberculosis treatment and ART) reducing free testosterone concentrations, despite normal total levels. After additional efavirenz was discontinued, SHBG returned to normal and his clinical symptoms fully resolved.
A 49-year-old heterosexual man who was diagnosed with HIV infection 3 years earlier following screening when hospitalised for pneumococcal pneumonia was managed with once daily darunavir 800 mg, ritonavir 100 mg and emtricitabine 200 mg/tenofovir disoproxil 245 mg. His current CD4 level was 370 cells/mm3 and viral load was <40 copies/ml. He trained regularly at the gym and was a keen amateur boxer. He wished to conceive with his wife but complained of lack of energy and reduced libido. Serum total testosterone levels were 5.5 pmol/l, calculated free testosterone 150 pmol/l, SHBG 14 nmol/l, FSH 4 IU/ml, LH 5 IU/ml and prolactin 89 mIU/ml. He admitted to regular use of oxandrolone and stanozolol over several years.