Portosinusoidal vascular disease (PSVD) is a rarely recognized liver condition caused by the involvement of small hepatic vessels. The diagnosis is established based on a set of clinical and/or histopathological criteria, with the absolute requirement of excluding liver cirrhosis through biopsy. Clinically, PSVD often presents with complications related to portal hypertension, although not all patients exhibit these signs. This article discusses the case of a 71-year-old patient with known splenomegaly, which had not been fully investigated and lacked a hematological explanation. The patient was evaluated for severe symptomatic microcytic anemia, likely secondary to portal hypertension, despite the absence of overt bleeding symptoms. During hospitalization, ligation of large, high-risk esophageal varices was performed, and no other sources of anemia were identified. Pre- or post-hepatic causes of portal hypertension were ruled out. Liver elastography results were within normal ranges, and liver function tests were normal except for a marginal isolated elevation of gamma-glutamyltransferase. Liver function remained intact. Liver biopsy findings were consistent with a diagnosis of PSVD. The patient did not have any identifiable associated conditions and was not taking any medications known to pose a risk. Therefore, treatment was focused solely on managing the complications of portal hypertension. Outpatient follow-up included the eradication of esophageal varices. Treatment with oral iron supplements led to the normalization of hemoglobin levels, which remained stable for months after the discontinuation of therapy, and liver function tests continued to be normal.