Post splenectomy related pulmonary hypertension

Table 1 Medical complications after splenectomy

Early

Lower lobe collapse of left lung

Left pleural effusion

Pneumonia

Venous thromboembolism

Subphrenic abscess

Delayed

Overwhelming infections: bacterial (Streptococcus pneumoniae, Hemophilus influenzae, Staphylococcus aureus, Streptococcus group B, Salmonella species, Escherichia coli and other coliforms, Capnocytophaga canimorsus and rarely Pseudomonas aeruginosa), parasitic (Babesiosis Plasmodium species, Ehrlichiosis)

Venous thromboembolism

Pulmonary hypertension

Graft vs host disease[61]

Table 2 World Health Organization's classification of pulmonary hypertension[10]

Group I - PAH

Idiopathic PAH

Heritable PAH (BMPR2, ALK1, ENG, SMAD9, CAV1, KCNK3, Unknown)

Drug and toxin induced

Associated with (1) Connective tissue disease; (2) HIV infection; (3) Portal hypertension; (4) Congenital heart disease; and (5) Schistosomiasis

Pulmonary veno-occlusive disease and/or pulmonary capillary hemangiomatosis

Persistent pulmonary hypertension of the newborn

Group II - Pulmonary hypertension due to left heart disease

Left ventricular systolic dysfunction

Left ventricular diastolic dysfunction

Valvular disease

Congenital/acquired left heart inflow/outflow tract obstruction and congenital cardiomyopathies

Group III - Pulmonary hypertension due to lung diseases and/or hypoxia

Chronic obstructive pulmonary disease

Interstitial lung disease

Other pulmonary diseases with mixed restrictive and obstructive pattern

Sleep-disordered breathing

Alveolar hypoventilation disorders

Chronic exposure to high altitudes

Developmental lung disease

Group IV - Chronic thromboembolic pulmonary hypertension

Group V - Pulmonary hypertension with unclear multifactorial mechanisms

Hematologic disorders: chronic hemolytic anemia, myeloproliferative disorders, splenectomy

Systemic disorders: sarcoidosis, pulmonary histiocytosis, lymphangioleimyomatosis

Metabolic disorders: glycogen storage disease, Gaucher’s disease, hypothyroidism

Others: tumoral obstruction, fibrosing mediastinitis, chronic renal failure, segmental pulmonary hypertension

Adapted from Galiè et al[62]. BMPR: Bone morphogenic protein receptor type II; CAV1: Caveolin-1; ENG: Endoglin; HIV: Human immunodeficiency virus; PAH: Pulmonary arterial hypertension.

Table 3 List of splenectomy and pulmonary hypertension studies

Ref.	Patient cohort (n)	Study design	No. of patients with splenectomy	Method of PH diagnosis	Comment
Hoeper et al[8]	Unexplained PHTN (61)	Retrospective	7	RHC	3 patients had splenectomy for hereditary spherocytosis and trauma, one patient with ITP
Jaïs et al[11]	CTEPH (257)	Retrospective	22 (8.6%)	RHC	15 patients had splenectomy after trauma, 4 with hemolytic disorder
Jaïs et al[11]	Idiopathic PHTN (276)	Retrospective	7 (2.5%)	RHC	Lower prevalence of splenectomy in idiopathic PHTN compared to prior study
Phrommintikul et al[38]	PHTN in Thalassemia with Hb < 10 g/dL (29)	Retrospective	29 (75.8%)	TTE	Increased prevalence of PHTN with higher nucleated red cells, platelets and transfusion requirement in splenectomised patients than those with intact spleen
Elstein et al[16]	Gaucher’s disease (134), 9 patients had PH	Retrospective	6	TTE	All patients with PHTN had enzyme replacement therapy
Stewart et al[15]	Hereditary stomatocytosis after splenectomy (9)	Retrospective	9	2 RHC	3 patients developed CTEPH, one portal hypertension
				1 on autopsy
Palkar et al[63]	PHTN after splenectomy (9)	Retrospective	9	RHC	4 patients belonged to group 1, two to group 4 and one each in groups 2, 3 and 5

RHC: Right heart catheterization; TTE: Transthoracic echocardiography; ITP: Immune thrombocytopenic purpura; PHTN: Pulmonary hypertension.