The 24-year-old lifted a combined total of 385 kilograms in the under 105kg competition on July 15, the final day of the weightlifting competition, to win the South American country's first gold medal of the Games.

He failed a test following the competition, it has been widely reported, with formal confirmation expected soon from the Pan American Sports Organization (PASO).

This would mean that Brazil's Mateus Gregorio Machado would be promoted to gold, while Ecuador's Guadalajara 2011 Pan American Games champion Jorge Arroyo would move from bronze to silver.

The athlete who originally finished in fourth place however, American-born Brazilian, Patrick Mendez has already failed a doping test for the second time in his career, meaning fifth-placed Cuban Alejandro Cisnero would receive bronze.

PASO have also confirmed that NIcaraguan wrestler Rene Silva, the 29-year-old who finished fifth in the under 125kg Greco Roman competition, failed a test for anabolic steroid boldenone and has been disqualified from the Games.

A further 10 cases have been officially confirmed, including Peru's swimmer Mauricio Fiol, who admitted on Facebook to testing positive for the anabolic steroid stanozolol following his silver medal in the men's 200 metres butterfly.

Argentinean wrestler Luz Vazquez has also been stripped of her under 69 kilograms bronze.

Two other wrestlers, Nicaragua's Elverine Jimenez and Paraguay's Stephanie Bragayrac, also failed along with three baseball players, Mario Mercedes Castillo of the Dominican Republic, Puerto Rico's Nelson Gomez and Colombia's Javier Ortiz, Honduras boxer Merin Zalazar Aranda and Mexican weightlifter Cynthia Dominguez.

Five other cases have not yet been officially confirmed by PASO but have been revealed by the relevent National Olympic Committees.

These include Puerto Rico volleyball player Sheila Ocasio, who failed for anabolic steroid stanozolol.

Chilean cyclist Carlos Oyarzun, a Guadalajara 2011 bronze medalist, failed a pre-competition test for FG4592, a compound known informally as "oxygen in a pill".

Another Chilean, marathon runner Christopher Guajardo, a Paralympic gold medallist at London 2012 as a guide for a visually impaired runner, failed for erythropoietin (EPO). 

The failure which has generated most attention involved Colombian cyclist Maria Luisa Calle, a 46-year-old veteran who controversially won a bronze medal in the Olympic points race at Athens 2004 only to be stripped of it before it was returned after the test was found to be faulty.

She failed for growth hormone enhancer GHRP2 after finishing fourth in the team pursuit.

Guatemalan weightlifter Astrid Camposeco also returned home having been notified on July 9 that a drugs test on May 23 was positive.

Although there is a history of doping cases at the Pan American Games, this number of 17 marks a significant increases on the four cases registered at each of the last two Games at Rio 2007 and Guadalajara 2011.

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