Two Cases of Late Diagnosis Pituitary Stalk Interruption Syndrome and Literature Review

Abstract

Background: Pituitary stalk interruption syndrome (PSIS) is a rare congenital condition that includes the triad of a thin pituitary stalk, an ectopic posterior pituitary gland, and an absent or hypoplastic anterior pituitary gland and is usually diagnosed in infancy. This report presents two cases of late diagnosis of PSIS and a literature review of the relevant cases. The objective is to update data on such an uncommon syndrome to avoid the consequences of pituitary dysfunction including short stature, impaired cognitive function, negative impact on bone health, adrenal crises and delayed puberty.

Case report: In this paper, we report on two cases of late diagnosis of PSIS with a history of growth hormone deficiency. The first case is a 21-year-old female presenting with generalized fatigability, dizziness and delayed puberty, while the second case is a 19-year-old female presenting with secondary amenorrhea. The hormonal profile of the first patient revealed panhypopituitarism; the second case had growth hormone deficiency subsequently had secondary hypogonadism with intact thyroid and adrenal functions. The diagnosis of PSIS was confirmed by magnetic resonance imaging (MRI), and both cases were treated with hormone supplements. Progress was also tracked through planned follow-up sessions. To the best of our knowledge, this is the first case series of such late diagnosis PSIS from Saudi Arabia.

Conclusion: The key message of this paper is that rare etiologies such as PSIS should be kept in mind, especially for young patients presenting with clinical evidence of pituitary hormonal deficiencies, and MRI should be considered to confirm diagnosis. The early diagnosis, hormonal replacement, and long-term follow-up are crucial to reducing negative impacts of pituitary hormonal deficiencies.

Keywords: PSIS; combined pituitary hormone deficiency; growth hormone deficiency; pituitary stalk interruption syndrome.

Figure 1

Pituitary MRI Image for Case number 1 revealed agenesis of the pituitary stalk associated with a high oval-shaped T1 signal on the sagittal image in the posterior aspect of the pituitary fossa, a finding that is in keeping with posterior ectopic pituitary (Yellow arrow). In addition, the clivus showed a superior soft tissue band in contact with the sphenoid sinus, with minimal peripheral enhancement (possibly non-fused sphenoid-occipital synchondrosis) (Blue arrow). Normal homogenous brain parenchyma, normal brain structures, a normal ventricular system, and no mass effect or midline shift were observed.

Figure 2

Pituitary MRI Image for Case number 2 revealed a triad of hypoplastic anterior pituitary, ectopic posterior pituitary (Yellow arrow) with an absent pituitary stalk, and characteristics of pituitary stalk interruption syndrome.

Figure 3

Flowchart studies included in the review.