Ben Ish Chai: Lashon harah about yourself?

Ben Ish Chaim (Torah Leshma #409): Question: Is it permitted to speak lashon harah about yourself? Reuven has a visible blemish on his body and he was discussing this blemish with a group of people. Shimon commented that he also had a blemish on his body but that it was covered up. Another person told Shimon that revealing that information was lashon harah since it served no purpose and no one knew about his hidden blemish – so why should he reveal it to others? Shimon responded that since he was testifying about himself and not others – it is not included in the prohibition of lashon harah. Is Shimon correct or not? Answer: There is no question that Shimon did something improper by revealing the existence of a hidden blemish – even though the blemsih he revealed was his own and not that of others. The proof for this is the Yevamos (64b), “The Rabbis told Rav Aba bar Zabda that he should get married to another wife and have children. He responded that if he had the merit he would have had children with his first wife. This in fact was not true but he wanted to conceal the fact that he had become impotent from attending the long lectures of Rav Huna where he was not able to urinate during the time of the lecture.” We see that he concealed the problem and did not want to reveal that he was impotent even to the Rabbis who were his peers who were pressuring him to get married. Nevertheless we see that he did not reveal that he was impotent....
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 I am not sure how this is evidence to justify his point. The  gemora itself reveals by names that a number of scholars became impotent because of Rav Huna's lectures and in addition it concludes with Rav Acha who said that the whole group of 60 students became impotent except for himself. Why isn't that lashon harah according to the Ben Ish Chai since it was said about others? If it is permitted to relate this information about others than why should it be considered lashon harah when said about yourself?


Yevamos (64b): With regard to the assumption that ‘it is possible that it was he who was unworthy to have children from her’, is it not possible that it was she who was unworthy? — Since she is not commanded to fulfil the duty of propagation she is not so punished. But surely it is not so! For the Rabbis once said to R. Abba b. Zabda, ‘Take a wife and beget children’, and he answered them, ‘Had I been worthy I would have had them from my first wife’! — There he was merely evading the Rabbis; for, in fact, R. Abba b. Zabda became impotent through the long discourses of R. Huna.     R. Giddal became impotent through the discourses of R. Huna;20 R. Helbo became impotent through the discourses of R. Huna, and R. Shesheth also became impotent through the discourses of R.Huna.  R. Aha b. Jacob was once attacked by dysuria, and when he was supported on the college cedar tree a discharge issued like a green palm shoot.  R. Aha b. Jacob stated: We were a group of sixty scholars, and all became impotent through the long discourses of R. Huna; with the exception of myself who followed the principle, Wisdom preserveth the life of him that hath it.