Bacterial variants in urinary casts and renal epithelial cells

Area of Science:

• Nephrology
• Microbiology
• Pathology

Background:

• Renal Fanconi's syndrome is a complex kidney disorder.
• Urinary casts with prominent granules were observed in a pediatric patient.

Observation:

• Granules within urinary casts transformed into filamentous bacterial variants over several days.
• These variants exhibited morphology consistent with streptococcal forms.
• Special blood cultures revealed bacterial variants that reverted to coccal forms, unlike conventional cultures.

Findings:

• Bacterial variants were identified in urine casts and within renal pelvic epithelial cells.
• The observed variants matched the morphology and staining of granules.
• Cryptic bacterial parasitization is proposed as a mechanism in nephropathies.

Implications:

• Bacterial variants may produce toxins and immunogens.
• These could contribute to glomerular and microcirculatory damage in kidney diseases.
• This finding suggests a novel pathogenic pathway in nephropathies.