Hypogonadism due to Testicular Failure: The low total testosterone level (14.7nmol/L) in conjunction with an elevated LH level (11.4 IU/L) suggests primary hypogonadism, where the testes do not produce enough testosterone, leading to an increase in LH as the pituitary gland tries to stimulate the testes to produce more testosterone.

Obesity-related Hypogonadism: Low testosterone can be associated with obesity, which can also affect SHBG levels. Although the SHBG level is provided, the impact of obesity on the hypothalamic-pituitary-gonadal axis could lead to a mixed picture of primary and secondary hypogonadism.
Secondary Hypogonadism: Despite the elevated LH, which typically points towards primary hypogonadism, the possibility of secondary hypogonadism (where the pituitary does not produce enough LH/FSH) cannot be entirely ruled out without further evaluation, especially considering the age of the patient and potential for pituitary issues.

Pituitary Tumor: Although the LH level is elevated, which is less common in pituitary tumors causing hypogonadism (as they typically lead to secondary hypogonadism with low LH), a non-functioning pituitary tumor could potentially disrupt normal pituitary function, leading to an atypical presentation.
Hemochromatosis: This genetic disorder can lead to iron overload, which can damage the pituitary gland and testes, resulting in hypogonadism. It's crucial to consider this diagnosis due to its potential for serious complications if left untreated.

Klinefelter Syndrome: Typically diagnosed in younger males, Klinefelter syndrome (47,XXY) is a cause of primary hypogonadism. Although rare in a 49-year-old presenting for the first time, it's a consideration if there are other suggestive clinical features.
Myotonic Dystrophy: A genetic disorder that can affect testicular function among other systemic manifestations. It's a rare cause of hypogonadism but should be considered if there are other symptoms suggestive of myotonic dystrophy.