Bisalbumin (fast and slow type) induced by human pancreatic juice

Human serum albumin variants in China: a molecular epidemiological investigation and literature review

Background

Bisalbuminemia is a hereditary and/or acquired abnormality characterized by a double albumin (ALB) band on serum protein electrophoresis. However, there have been no epidemiological investigations of ALB variants in Chinese populations.

Methods

This retrospective study examined 71,963 unrelated subjects from five provinces in southern China. ALB variants were screened by cellulose acetate electrophoresis at pH 8.6 and ALB mutations were confirmed by polymerase chain reaction-DNA sequencing.

Results

The average incidence of inherited bisalbuminemia in the southern Chinese population was 0.0264% (19/71,963). Thirteen cases showed slow and six showed fast genetic variants on cellulose acetate electrophoresis. Four kinds of ALB variants were identified: proalbumin Lille (p.Arg23His), ALB Castel di Sangro (p.Lys560Glu), ALB Fukuoka-1 (p.Asp587Asn), and a novel ALB Wuxi (p.Lys562Glu). The gene frequency of ALB variants in the Wuxi region (0.126%, 13/10,297) was significantly higher than in other regions in southern China, and 90.9% (10/11) of cases of proalbumin Lille were also found in the Wuxi region.

Conclusions

This study provides the first report of the detailed prevalence and molecular characterization of ALB variants in southern China. Compared with other areas of China, Wuxi had a different pattern of ALB variants and a high prevalence of proalbumin Lille.

Bisalbuminemia: A Pathologist's Insight of an Uncommon Phenomenon

Background The incidence of a bifid electrophoretic pattern in the albumin region on serum protein electrophoresis is an infrequent phenomenon. The availability of literature from India is scarce and is limited to case reports. Objective The aim of the study is to analyze the frequency of bisalbuminemia in an Indian referral facility. The study delved into their clinical associations. Material and Methods The retrospective case records of the patient from the departmental database were scrutinized. The study subjects were for an 8-year study period. Results There were about 39,900 serum electrophoresis performed in an 8-year study period. A total of 40 cases of bisalbuminemia were detected. The incidence in our cohort was 0.01%. Conclusion Bisalbuminemia, an overtly benign condition, is infrequent in Indian population although not rare. It is associated with several clinical disorders; however, the association seems to be plausibly coincidental.

Albumin as marker for susceptibility to metal ions in metal-on-metal hip prosthesis patients

Metal-on-metal (MoM) hip prostheses are known to release chromium and cobalt (Co), which negatively affect the health status, leading to prosthesis explant. Albumin (ALB) is the main serum protein-binding divalent transition metals. Its binding capacity can be affected by gene mutations or modification of the protein N-terminal region, giving the ischaemia-modified albumin (IMA). This study evaluated ALB, at gene and protein level, as marker of individual susceptibility to Co in MoM patients, to understand whether it could be responsible for the different management of this ion. Co was measured in whole blood, serum and urine of 40 MoM patients. A mutational screening of ALB was performed to detect links between mutations and metal binding. Finally, serum concentration of total ALB and IMA were measured. Serum total ALB concentration was in the normal range for all patients. None of the subjects presented mutations in the investigated gene. Whole blood, serum and urine Co did not correlate with serum total ALB or IMA, although IMA was above the normal limit in most subjects. The individual susceptibility is very important for patients’ health status. Despite the limited results of this study, we provide indications on possible future investigations on the toxicological response to Co.

Three truncated forms of serum albumin associated with pancreatic pseudocyst

Plasma from a patient with chronic pancreatic pseudocyst showed an additional more negative albumin band (18%) on agarose gel electrophoresis. Both components bound (63)Ni(2+), indicating intact N-terminals; however, electrospray ionisation analysis of the intact proteins showed the mass of more negative albumin was 1254 Da less than the control and that the apparently normal band was 112 Da less. Reverse phase mapping and mass analysis of CNBr peptides showed three proteolytically modified forms of the C-terminal peptide indicating that some 81% of the albumin molecules lacked the C-terminal Leu residue, that 18% lacked the C-terminal KKLVAASQAALGL and that approximately 1% lacked the QAALGL sequence. These findings were further verified by tryptic mapping of the aberrant CNBr peptides. The truncations probably result from exposure of the albumin to 'leaking' pancreatic endo and exoproteases. During less acute phases of the disease, the 13 and 6 residue truncated forms together decreased to less than 1%, while the des-Leu(585) form made up the balance; no normal albumin was detected. This suggested that the des-Leu(585) form might be present at low levels in the plasma of normal individuals and CNBr mapping confirmed that it constituted 4-15% of the albumin from normal plasma.

Bisalbuminuria in an adult with bisalbuminemia and nephrotic syndrome

Bisalbuminemia (or alloalbuminemia) is a relatively rare hereditary or acquired condition characterized by the presence of two distinct albumin bands, or, less commonly, a single widened albumin band, after agarose gel electrophoresis of serum. Bisalbumins are caused by point- or chain-mutations that occur with a population frequency of 1:10,000 to 1:1000. Although no adverse clinical effects have been attributed to bisalbumins, some albumin variants have altered affinity for steroid hormones, thyroxine, or drugs. We report a case of bisalbuminuria in a 25-year-old man with bisalbuminemia and nephrotic syndrome.