Presentation in adulthood is rare, but should be considered when dealing with cases of hypoparathyroid hypocalcemia. 

Introduction:

DiGeorge Syndrome has an estimated prevalence of 1 in 4,000-6,000 live births, making it one of the most common genetic disorders \cite{Devriendt1998}.
The syndrome is due to a microdeletion of chromosome 22q11.2, and less commonly 10p13. Deletion can be inherited but more typically occurs as a de novo event. If a parent has a deletion, risk to each child is 50%. However, 22q11.2 deletions have been found in only 28% of parents of the affected people \cite{Ryan1997}. The syndrome is associated with failure of development of the third and fourth branchial pouches \cite{Robinson1975}. It's been suggested that there is a failure of or aberrant migration of the neural crest during the fourth week of embryogenesis \cite{Mølsted2010}
The syndrome can be classified as partial or complete. Complete DGS describes patients with DGS who are athymic or have no circulating T cells (less than 1% of all DGS cases). Those with partial DGS have thymic hypoplasia, evidenced by presence of circulating T cells \cite{Müller1989}.  

Case Report: 

Patient is a 30-year-old female presented to the hospital with worsening fatigue, malaise, facial/perioral/tongue numbness, and a tingling sensation all over her body. The patient said she's been experiencing the weakness and numbness, on and off, for the past several years. Minor cramps of the hands and legs are also associated with the numbness.
Past medical history included congenital heart disease (coarctation of aorta, VSD), vitiligo, neuropathic pain, bipolar disorder, anxiety, and learning disabilities. Patient has been vitamin D deficient since 2017. She had a prescription for ergocalciferol (vitamin D2) 50,000 units, but has been out of her vitamins for two months. This was her first hospitalization related to fatigue and numbness.
On physical exam, there was mild facial dysmorphism including a long face and bulbous nose. She displayed a positive Chovstek's and Trousseau's sign. 
Laboratory values revealed a serum calcium level of 6.3 mg/dL, ionized calcium of 3.4 mg/dL, phosphorus 3.4 mg/dL, vitamin D of 28.9 ng/mL, and PTH of 44.2 pg/mL. The expected rise in PTH due to vitamin D deficiency was not present, suggesting a possible diagnosis of hypoparathyroidism. The hemoglobin was 10.4, white blood cell count 2.98, and platelets 120,000. A chronic pancytopenia of at least 4 years was noted per chart review. Negative ANA, HIV, Hepatitis panel, EBV. Zinc and copper levels were within normal limits. Liver enzymes were slightly elevated with an AST of 53 and ALT of 112. An abdominal ultrasound revealed hepatic steatosis. FISH analysis detected a deletion of TBX1 (22q11.21), supporting a diagnosis of velocardiofacial syndrome (VCFS).

Literature Review

Other Documented Case Studies: