An outline of “Malignant Hypertension” with treatment

Malignant hypertension is a rare but very serious form of high blood pressure with systolic and diastolic blood pressures usually greater than 240 and 120 mm Hg respectively which develops as such or as a late phase consequence of benign hypertension. It is characterized by not only very elevated blood pressure but also organ damage in the eyes, brain, lung and/or kidneys. It differs from other complications of hypertension by the presence of papilledema.

Causes- Like essential hypertension the exact cause of malignant hypertension is not completely understood. But the following may be considered as risk factors-
(1) Young age group is more prone to it than the old age group, which is just reverse of essential hypertension.
(2) African heritage individuals are at higher risk of developing it.
(3) Any individual with a history of kidney failure or renal artery stenosis is more prone to it.
(4) Women with toxemia of pregnancy have an increased risk.

Pathology- Malignant hypertension is characterized pathologically by cellular hyperplasia & arteriolar necrosis in the renal arterioles. Most of the organ damage is caused by ruptures in small blood vessels in places.

Symptoms - The following symptoms, which may be present in a case of malignant hypertension are not exclusive to it & may also be present in a number of potentially serious medical conditions.
(1) Blurry vision.
(2) Nausea & vomiting.
(3) Chest pain.
(4) Seizures or fits.
(5) Decreased urine output.
(6) Weakness or strange tingling/numbness in the arms, legs, or face.
(7) Transient paralysis.
(8) Impairment of consciousness.
(9) Severe headaches.
(10) Shortness of breath.

Clinical features-
(1) Disproportionately high diastolic blood pressure.
(2) Haematuria.
(3) On funduscopic examination, besides general hypertensive changes, retinal haemorrhages, exudates & papilloedema are seen & are diagnostic of malignant hypertension.

Treatment- Malignant hypertension must be treated quickly to avoid serious organ damage and, possibly, death. But very rapid reduction of BP is unwise as it may precipitate cerebral, myocardial or renal infarction. Rather, it should be managed by slowly, preferably over about 24 hours, bringing diastolic blood pressure back to the range of 100-110 mm Hg. It may be done by using a combination of oral nifedipine & a Beta-Adrenergic blocker like atenolol. But when a more rapid reduction of BP is needed, intravenous nitroprusside is the first choice.

Prognosis- If untreated, malignant hypertension has a very poor prognosis with invariable death within the first year in most of the cases. All the major organ systems are at risk from the severe increases in blood pressure due to malignant hypertension, but the kidneys, eyes, and brain seem to be the most susceptible organs, especially the kidneys which are very much sensitive to elevations in blood pressure and permanent kidney damage is a common complication of untreated malignant hypertension.

Something regarding refractive errors of the eye

First of all we have to know what is the ideal refractive condition of the eye. The ideal refractive condition of the eye is known as emmetropia. So emmetropia may be defined as the refractive condition of the eye where parallel rays of light from infinity come to a focus on the retina, better to say on the fovea when accommodation is at rest. Any variation from this standard constitutes what is known as ametropia. So ametropia may be defined as the refractive condition of the eye where due to some refractive error, parallel rays of light from infinity do not come to a focus on the retina, better to say on the fovea when accommodation is at rest.

Types of refractive errors of the eye -

Hypermetropia-It is a type of refractive error of the eye where parallel rays of light from infinity come to a focus behind the retina when accommodation is completely relaxed. It is also called long-sightedness. Divergent rays from a near object are focused still further back.

Treatment- Treatment is by spherical convex lens. Ordinary spectacles may be used or contact lenses may also be used.

Myopia-It is a type of refractive error of the eye where parallel rays of light from infinity come to a focus in front of the retina when accommodation is at rest. It is also called short-sightedness.

Treatment- Treatment is by spherical concave lens. Ordinary spectacles may be used or contact lenses may also be used.

Astigmatism- It is a type of refractive error of the eye where parallel rays of light from infinity cannot converge to a point focus due to unequal refractions in different meridians of the optical system of the eye but form focal lines. Astigmatism may be regular where the refractive power changes uniformly from one meridian to the other. Astigmatism may also be irregular where the refractive power changes irregularly in different meridians of the optical system of the eye.

Treatment- Regular astigmatism may be treated both by ordinary cylindrical lenses or by contact lenses. But irregular astigmatism requires the use of contact lenses only.