Nephrotic Syndrome: This condition is characterized by excessive loss of protein in the urine, leading to low levels of globulins and a high albumin/globulin ratio. The kidneys' selective loss of albumin and retention of globulins result in this laboratory finding.

Liver Disease: Certain liver conditions, such as cirrhosis, can lead to decreased production of globulins, resulting in a low globulin level and a high albumin/globulin ratio. However, liver disease often presents with other abnormalities in liver function tests.
Malnutrition: Severe malnutrition can result in decreased production of proteins, including globulins, leading to an altered albumin/globulin ratio.
Hemodilution: Conditions leading to hemodilution, such as excessive fluid resuscitation, can dilute the concentration of globulins, potentially altering the albumin/globulin ratio.

Multiple Myeloma: Although multiple myeloma often presents with an elevated globulin level due to the production of monoclonal proteins, some cases can have a normal or low globulin level, especially if there is significant renal impairment or if the myeloma produces light chains that are not detected by standard protein electrophoresis. Missing this diagnosis could be fatal due to the aggressive nature of the disease and its potential for renal failure and other complications.
Amyloidosis: This condition involves the deposition of abnormal proteins in various tissues and can lead to renal failure and altered protein levels, including a potential decrease in globulins.

Selective Immunoglobulin Deficiency: Rare conditions where there is a deficiency in one or more classes of immunoglobulins can lead to low globulin levels. These conditions are often associated with recurrent infections.
Genetic Disorders Affecting Protein Synthesis: Certain genetic disorders can affect the production of proteins, including globulins, leading to abnormal levels and ratios. These are rare and often present with other systemic manifestations.