Roth Spots

Etiology

Historically, Roth spots were considered to be a pathognomonic finding for bacterial endocarditis secondary to septic emboli within the retina. Given recent histological data, it is now believed that Roth spots are the result of retinal capillary rupture and intraretinal hemorrhage. Roth spots occur in a multitude of disease processes in which retinal blood vessel injury and subsequent bleeding and hemorrhage occur. A common thread found in these conditions is a predisposition for endothelial dysfunction allowing for retinal capillary disruption. Histological examination reveals that the white centered lesions are composed mostly of fibrin, which represents a fibrin-platelet plug at the site of vessel rupture.[4]

Epidemiology

White centered retinal hemorrhages are a nonspecific ophthalmologic finding seen in multiple systemic conditions of various etiologies.  Roth spots are seen on fundoscopic examination and tend to be located in the peripheral or posterior poles of the eyes. Retinal endothelial dysfunction appears to be a common thread among the diverse causes of white centered retinal hemorrhage. The differential diagnosis of Roth spots is vast and includes:

• Bacterial endocarditis
• Anemia/thrombocytopenia
• Collagen vascular disease
• Leukemia
• Hypertensive retinopathy
• Diabetic retinopathy
• Pre-eclampsia
• Human Immunodeficiency Virus (HIV)
• Anoxia
• Shaken baby syndrome

Pathophysiology

While multiple theories have been proposed to explain the pathogenesis of white centered retinal hemorrhages, the most widely accepted is that of retinal capillary rupture and intraretinal hemorrhage. Retinal capillary rupture occurs as a result of endothelial cell dysfunction. Extravasation of red blood cells follows vessel rupture with subsequent activation of the clotting cascade and formation of a platelet-fibrin plug at the site of the damaged endothelium. Histological studies revealed the whites lesions are composed primarily of platelet-fibrin thrombi.

History and Physical

Retinal hemorrhage is commonly seen in patients with underlying disease processes that predispose to retinal endothelial dysfunction and rupture.  Roth spots may be seen on a routine ophthalmologic exam in asymptomatic patients prompting further diagnosis and evaluation. However, patients may also present with signs and symptoms of systemic illness and retinal hemorrhages noted during acute evaluation. The presence of Roth spots on physical examination should prompt the physician to evaluate for an underlying systemic disease. The clinician should take a thorough history and complete a careful physical exam.[5][6]

A detailed history with a full review of the system can help to narrow the differential diagnosis and identify the underlying disease process. Attention must be paid to symptoms associated with the more common etiologies of Roth spots. Symptoms of endocarditis and infection including fever, chills and night sweats must be reviewed. Symptoms commonly seen in hematologic disease should also be assessed such as unexplained weight loss, fatigue, abnormal bleeding or bruising and shortness of breath.  Review of personal past medical history, as well as family history, may also be helpful in determining the etiology.

Roth spots are seen on fundoscopic examination. A complete ophthalmologic examination should be performed as other retinal abnormalities may accompany Roth spots. After Roth spots are identified, the physician must carefully examine the patient to assess for physical signs of systemic illness. It is important to note the patient's vital signs, particularly blood pressure, temperature, and pulse. Several etiologies of white-centered retinal hemorrhages have classical physical examination findings associated with them; therefore, the physician must have a high index of suspension during the examination. In patients that present with concerns for endocarditis and Roth spots, the clinician must carefully examine for other stigmata of endocarditis including Janeway lesions, Osler nodes, splinter hemorrhages, petechiae and cardiac murmurs. Assessment of digital clubbing, the presence or absence of splenomegaly and respiratory abnormalities is also helpful.[7][8]

Evaluation

The initial evaluation is based largely on results of a thorough history and physical examination. A complete blood count with differential to assess for leukocytosis, anemia, and thrombocytopenia along with other hematologic abnormalities should be completed in all patients. A fasting plasma glucose or hemoglobin A1C to assess for diabetes mellitus should be performed. If infectious etiology is suspected erythrocyte sedimentation rate, C-reactive protein and blood cultures may be indicated. A transthoracic echocardiogram is an important initial diagnostic test if endocarditis is suspected. Additional tests such as HIV antibody testing, imaging studies or peripheral blood smear should be considered if indicated based on presenting symptoms and physical examination findings.

Treatment / Management

Roth spots are most often asymptomatic and detected during a routine dilated eye examination. Visual disturbance due to Roth spots is rare but can occur with macular involvement. The majority of white centered retinal hemorrhages will resolve without intervention. Treatment is aimed at the underlying cause and is often supportive. The most important management consideration in patients with Roth spots is the identification of the causative etiology to prevent possible ocular and systemic complications that may occur due to the underlying disease. Follow-up with an ophthalmologist is an important consideration in patients in whom Roth spots are discovered during acute illness. [9]

Differential Diagnosis

• Anaemia

• Anoxia

• CO Poisoning

• Complicated Labor

• Diabetic Retinopathy

• HIV Retinopathy

• Hypertension

• Intracranial Hemorrhage

• Preeclampsia

• Shaken Baby Syndrome

• Subacute Bacterial Endocarditis