Orthostatic albuminuria, also known as orthostatic proteinuria is defined by raised levels of urine protein excretion while in an upright position. In orthostatic albuminuria urine protein excretion returns to normal while in a supine position, such as laying down. Orthostatic albuminuria is the most common cause of isolated proteinuria in those under 20.[5] The prevalence of orthostatic albuminuria is suspected to be between 2 and 5%,[6] however some studies suggest that it is more common.[7] Orthostatic albuminuria is diagnosed if urine protein levels are normal in a morning urine sample and there are no other obvious causes of albuminuria.[8] Patients with orthostatic albuminuria are often asymptomatic and there is no indication for any type of treatment or interventions.[4]
| Orthostatic albuminuria | |
|---|---|
| Other names | Orthostatic proteinuria, Postural proteinuria, Postural albuminuria. |
 | |
| The structure of Human serum albumin (HSA) complexed with 6 palmitic acid molecules | |
| Pronunciation | |
| Specialty | Urology  |
| Usual onset | Under 30 years old.[3] |
| Diagnostic method | Urine test strip, Urine protein/creatinine ratio, 24 hour urine collection, renal function tests, and urine microscopy.[3] |
| Differential diagnosis | Transient proteinuria.[4] |
| Prognosis | Benign.[3] |
| Frequency | 3 to 5% of adults and teenagers.[3] |
Causes
editThe exact causes of orthostatic albuminuria are unknown however three different theories have been proposed, a normal variant, subtle glomerular abnormalities, exaggerated hemodynamic response, and left renal vein entrapment.[9]
Diagnosis
editThere is no standard test for orthostatic albuminuria. Physical examination as well as a past medical history can help determine the extent of symptoms in some individuals. Urine analysis, urine cytology, complement activity, urine culture, and serological studies can help differentiate orthostatic albuminuria from other causes of proteinuria. Recumbent and upright urine protein to creatinine ratio is often used as a screening test. 24-hour split urine testing is often tested.[10]
Additional causes of albuminuria include glomerulopathy, acute tubular necrosis, Alport syndrome, toxins, proximal renal tubular acidosis, diabetes mellitus, malignancies, polycystic kidney disease, infections, and chronic kidney disease.[8]
Outlook
editThe long-term prognosis of orthostatic albuminuria hasn't yet been established. Based on current research, it seems that orthostatic albuminuria is a benign condition and typically resolves spontaneously within a couple years.[11]
See also
editReferences
edit- ^ "Definition of Orthostatic". Merriam-Webster. November 10, 2023. Retrieved November 24, 2023.
- ^ "albuminuria". Oxford English Dictionary. Oxford University Press. July 2023. Retrieved 24 November 2023.
- ^ a b c d Moses, Scott (February 17, 2017). "Orthostatic Proteinuria". Family Practice Notebook. Retrieved November 24, 2023.
- ^ a b "UpToDate". UpToDate. Retrieved November 24, 2023.
- ^ Uehara, K.; Tominaga, N.; Shibagaki, Y. (May 25, 2014). "Adult orthostatic proteinuria". Clinical Kidney Journal. 7 (3): 327–328. doi:10.1093/ckj/sfu040. ISSN 2048-8505. PMC 4377758. PMID 25852903.
- ^ Mazzoni, M. B. M.; Kottanatu, L.; Simonetti, G. D.; Ragazzi, M.; Bianchetti, M. G.; Fossali, E. F.; Milani, G. P. (July 23, 2010). "Renal vein obstruction and orthostatic proteinuria: a review". Nephrology Dialysis Transplantation. 26 (2): 562–565. doi:10.1093/ndt/gfq444. ISSN 0931-0509. PMID 20656752. Retrieved November 24, 2023.
- ^ Vehaskari, V. Matti; Rapola, Juhani (1982). "Isolated proteinuria: Analysis of a school-age population". The Journal of Pediatrics. 101 (5): 661–668. doi:10.1016/s0022-3476(82)80287-4. ISSN 0022-3476. PMID 7131137. Retrieved November 24, 2023.
- ^ a b AK, Leung; AH, Wong; SS, Barg (2017). "Proteinuria in Children: Evaluation and Differential Diagnosis". American Family Physician. 95 (4): 248–254. ISSN 1532-0650. PMID 28290633. Retrieved November 24, 2023.
- ^ Ingold, Curtis J.; Bhatt, Harshil (August 8, 2023). "Orthostatic Proteinuria". StatPearls Publishing. PMID 32965979. Retrieved November 24, 2023.
- ^ Kovvuru, Karthik; Kanduri, Swetha R.; Thongprayoon, Charat; Cheungpasitporn, Wisit (2020). "Diagnostic approach to orthostatic proteinuria: a combination of urine micro-proteinuria with ultrasonography of the left renal vein". Annals of Translational Medicine. 8 (12): 779. doi:10.21037/atm.2020.02.50. ISSN 2305-5839. PMC 7333150. PMID 32647704.
- ^ Arslan, Zümrüt; Koyun, Mustafa; Erengin, Hakan; Akbaş, Halide; Aksoy, Gülşah Kaya; Çomak, Elif; Akman, Sema (May 11, 2020). "Orthostatic proteinuria: an overestimated phenomenon?". Pediatric Nephrology. 35 (10): 1935–1940. doi:10.1007/s00467-020-04586-4. ISSN 0931-041X. PMID 32394189. S2CID 218592496. Retrieved November 24, 2023.
Further reading
edit- Vehaskari, V M (October 1, 1982). "Orthostatic proteinuria". Archives of Disease in Childhood. 57 (10): 729–730. doi:10.1136/adc.57.10.729. ISSN 0003-9888. PMC 1627924. PMID 7138061.
- von Bonsdorff, Martin; Törnroth, Tom; Pasternack, Amos (1982). "Renal Biopsy Findings in Orthostatic Proteinuria". Acta Pathologica Microbiologica Scandinavica, Series A. 90A (1–6): 11–18. doi:10.1111/j.1699-0463.1982.tb00058_90a.x. ISSN 0108-0164. PMID 7080809. Retrieved November 24, 2023.
- Brandt, John Robert; Jacobs, Aaron; Raissy, Hengameh H.; Kelly, Franceska Marie; Staples, Amy Otten; Kaufman, Ellen; Wong, Craig Stephen (February 18, 2010). "Orthostatic proteinuria and the spectrum of diurnal variability of urinary protein excretion in healthy children". Pediatric Nephrology. 25 (6): 1131–1137. doi:10.1007/s00467-010-1451-z. ISSN 0931-041X. PMC 3677044. PMID 20165888.
- Vehaskari, V. Matti (1990). "Mechanism of orthostatic proteinuria". Pediatric Nephrology. 4 (4): 328–330. doi:10.1007/bf00862510. ISSN 0931-041X. PMID 2206899. S2CID 26930865. Retrieved November 24, 2023.
- Sebestyen, Judith F.; Alon, Uri S. (September 13, 2010). "The Teenager With Asymptomatic Proteinuria: Think Orthostatic First". Clinical Pediatrics. 50 (3): 179–182. doi:10.1177/0009922810380904. ISSN 0009-9228. PMID 20837623. S2CID 8219563. Retrieved November 24, 2023.