The former President is apparently suffering from sepsis, an infection that affects the entire body.
"Sepsis is when you start out with an infection in one part of your body, and that inflammatory process it engenders, takes over your entire body," said Dr. Puneet Patni, a pulmonary specialist with Kelsey-Seybold Clinics.
"For example, you may start with pneumonia, and then you get sepsis and your whole body gets inflamed. So that can cause dysfunction in a lot of organ systems," said Patni, who is not treating anyone in the Bush family.
A statement released Monday from Bush's office stated the former sitting president was admitted to Houston Methodist Hospital on Sunday morning "after contracting an infection that spread to his blood."
On Tuesday, Bush's spokesperson added that the former president is "responding and recovering." He added that updates will only be issued if something changes, and for now, the previous statement still stands.
For media planning purposes, the Office of @GeorgeHWBush will issue updates on #41 when we have something to update. Those updates would come through this Twitter feed first. Happily, our previous statement still stands: "responding and recovering."— Jim McGrath (@jgm41) April 24, 2018
The 93-year-old Bush was present for the public viewing Friday of his wife Barbara Bush at St. Martin's Episcopal Church. Barbara Bush passed away last Tuesday at 92.
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Patni says the former President's participation in public events is unrelated to the sepsis diagnosis.
"It would seem unlikely that shaking people's hands would have caused him to be this sick."
The following is the statement in full, released Monday by Bush chief of staff, Jim McGrath:
"President Bush was admitted to the Houston Methodist Hospital yesterday morning after contracting an infection that spread to his blood. He is responding to treatments and appears to be recovering. We will issue additional updates as events warrant."
Later Monday night, McGrath added that the former president has a goal to work toward:
"The 41st President wants to go to Maine this summer. He's the most goal oriented person on the planet and I would not bet against him."
Many Houstonians, including Mayor Sylvester Turner, are offering words of support.
"We're praying for George Bush, the former President," said the Mayor. "The city as a whole, we're praying that God will gird him, strengthen him so he can return home to his loved ones."
George H.W. Bush has faced varying medical issues in recent years, requiring stays of multiple days in the hospital. His recent stay was in April 2017 when he spent two weeks for pneumonia and chronic bronchitis.
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