This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
Lithaemia is a condition in which the blood contains an excess of uric acid or its salts, and is usually productive of such symptoms as insomnia, vertigo, tinnitus aurium, disagreeable fulness of the head, and general "nervousness." The urine becomes loaded with nitrogenous waste.
When uric acid appears in excess as a sediment in the urine it is very desirable that its formation should be checked, if possible, and that any crystals already deposited in the kidneys and bladder should be dissolved and eliminated. If the accumulation continues, the presence of crystals ("gravel ") gives rise to attacks of renal or vesical colic, causing intense agonising pain, and often haematuria. A majority of the different forms of calculi are composed wholly or in part of uric acid, and they may be formed in any part of the urinary system, which, in addition to the other symptoms, may possibly cause ulceration and inflammation of the mucous membrane or serious obstruction to the outflow of the urine. The exact mode of production of uric acid in the body is still a matter of uncertainty, but it is undoubtedly associated with nitrogenous metabolism. Nucleins are derived by digestion from peculiar nucleo-proteids which are contained chiefly in the thymus gland, liver, and spleen, but also in slight proportion in meat and meat extracts. Nucleins appear to be at least one of the principal sources of uric-acid formation. Tea, coffee, and cocoa are believed to aid in the process of uric-acid formation in some manner in the body, whereas milk, cheese, and eggs do not have that effect.
The final destination of uric acid is its conversion into urea, but from lack of perfect oxidation in the tissues this process is checked.
The indications for dietetic treatment are clearly, therefore, to reduce the animal foods in amount or temporarily withhold them altogether, while giving large quantities of plain water and of waters containing potassium or lithium salts to aid in dissolving the uric acid already existing in the kidneys or bladder, and promote its conversion into urea and hippuric acid.
Although the acidity of the urine is not caused by uric acid, but by acid sodium phosphate (Na2P04), the deposition of uric acid is accomplished in an acid menstruum, and it is well to reduce the urine temporarily to a neutral or even somewhat alkaline reaction.
Animal food, except milk, tends to make the urine acid, whereas milk and vegetable food favour alkalinity. In speaking of the lithic-acid diathesis in children, Fothergill wrote that "lean meat, raw meat minced, and beef tea are so much poison." Lithaemic headaches will often cease when the patient stops eating butcher's meat, cheese, etc., if excessive indulgence in animal food has been the previous habit. Peptonised food is worse, for the dyspepsia which often accompanies lithaemia is in a way a conservative process, checking the digestion of animal foods, whereas the predigested foods are more promptly and easily carried to the overburdened liver. Some lithaemic patients cannot take meat well in hot weather, but can do so at other seasons. But an excessive meat diet cannot be regarded as the sole cause of lithaemia; other factors are concerned, such as overeating and the abuse of saccharine food, which causes mal fermentation, deranges the functions of the liver, and alters the composition of both blood and urine.
Murchison declared that "habitual lithaemia often results from the patient taking more food than can be converted into tissue or disintegrated in the liver," and Sir Henry Thompson expressed his views in regard to sweets thus forcibly: " Sugar, in all its forms, at every meal, and wherever met with, forbid it altogether,... let fatty matters, butter, cream, and the fat of meat, whether simply cooked or in combination to form pastry, be taken very sparingly." This is the practice at Carlsbad also, and it reduces the work of the liver and kidneys. For some patients - especially the obese - it is more important than wholly eliminating meat from the regimen.
Murchison, who was among the first to advocate a rational dietetic treatment of habitual lithaemia, forbade all saccharine and oleaginous food, especially "made dishes," and highly seasoned foods, sauces, rich gravies, etc. In severe cases he advised giving up amylaceous foods as well, and forbade the eating of potatoes, rice, sago, fruits, etc., and bread was allowed only in moderation.
Many acids contained in fresh fruits, such as benzoic or quinic acid, have a favourable solvent action. These acids are found in the external cuticle of fresh fruits and vegetables, which may be eaten in cases of gravel. According to Lyman, eating raw, unpeeled apples in considerable quantities supplies potassium salts, which tend to increase the alkalinity of the blood, but sweet fruits, pears, grapes, plums, strawberries, etc., must not be indulged in.
Patients may eat abundantly of oatmeal, wheaten and Graham bread toasted, macaroni, fresh young peas, string beans, Lima beans, rice, spinach, asparagus, celery, lettuce, and other salads, except tomato (without oil). Meat should not be eaten oftener than once a day. Fresh fish, sweetbread, poultry, and game may be taken sparingly. No diet can be rigidly enforced in every case alike. Alexander Haig (Diet and Food) classifies as "uric-acid-free " foods, milk and its products, breadstuffs, cereals and glutens, nuts, vegetables, and fruits.
If lithaemia is present in young children after three or five years of age, they require a larger proportion of fat. They may have bread and butter with a little fat bacon, or a baked potato with butter, and puddings of bread, crackers, rice, or sago, but not of raw flour. They must not be offered sweets. They have poor appetites, and some variety must be prescribed, or they will lose weight and strength.
Some writers are disposed to attach less importance to dietetic errors as influencing lithaemia, and the cooking is far more important than the composition of the food. Reasonable variety, including proteid food, should be allowed, for "lithaemics do best on plenty of well-prepared food in the greatest variety according to the seasons" (L. C. Gray).
Various alkaline mineral waters are constantly prescribed for adults, and patients who can afford to take the course are benefited by the baths of Carlsbad, Vichy, Neuenahr, Ems, etc., but for those to whom travel is an impossibility and whose means do not allow them to purchase artificial mineral waters, very good substitutes are to be made by dissolving sodium carbonate or sodium phosphate in soda water or sour lemonade, or in plain water, in the proportion of from one to two drachms in three or four pints, to be taken in the course of the twenty-four hours, or two to five grains of the carbonate of lithium may be employed in the same way. Effervescent lithium tablets are now sold which may be added to a tumbler of water at the table and taken with meals.
Solution of the deposits, or at least the prevention of their increase, is aided by the free drinking of Londonderry, Buffalo, or other lithia waters, Vichy, Waukesha, etc., although it must be said of most so-called lithia waters that their use is chiefly that of pure water, for a barrelful would have to be drunk to obtain an ordinary medicinal dose of lithium.
Most patients do better without alcohol in any form. They may feel the loss of accustomed stimulation for a few months, but they should make a strong effort to give it up completely. Malt liquors and sweet wines, champagne, and spirits had better be absolutely forbidden, but if necessary, a little good sound claret or Scotch whisky in water may be drunk.
Gravel is much less common among habitual beer drinkers than among those whose daily beverage is wine. This is attributed by Moleschott to the greater acidity and larger proportion of alcohol in the latter. On the contrary, Ebstein holds that beer is not injurious in lithiasis, and tea also has some reputation in checking the deposition of uric acid. Coffee does no harm.