Are small colony variants responsible for fatal infections?

There are a few reports suggesting that small colony variants (SCVs) may be responsible for fatal infections. Some are given below.

1. Haussler et al. (2003). Fatal outcome of lung transplantation in cystic fibrosis patients due to small-colony variants of the Burkholderia cepacia complex. Eur J Clin Microbiol Infect Dis 22(4), 249-53.

2. Seifert et al. (1999). Fatal case due to methicillin-resistant Staphylococcus aureus small colony variants in an AIDS patient. Emerg Infect Dis 5(3), 450-3.

3. Adler et al. (2003). Emergence of a teicoplanin-resistant small colony variant of Staphylococcus epidermidis during vancomycin therapy. Eur J Clin Microbiol Infect Dis 22(12), 746-8.

In all these cases, it can be noted that the patients had long and complicated clinical histories and had received antibiotic therapy for a long time. For example, in the first case, the patients had severe lung diseases and had undergone lung transplantation whereas in the second article, it was an AIDS patient who had a traffic accident. Similarly, in the third case, the patient was undergoing treatment for acute myeloid leukemia. Antibiotic therapy might have selected SCVs, and both large and small colony forms were cultured in all cases. However, there are no indications that SCVs are responsible for the fatal infections in any of the above cases. Just because SCVs were isolated from these patients, how can it be suggested that they are responsible for fatal infection especially considering their severe and complicated clinical histories?