Renal pyramids

Palubinskas AJ (1963) Renal pyramidal structure opacification in excretory urography and its relation to medullary sponge kidney. Radiology 81 963-970 Patriquin HB, O Regan S (1985) Medullary sponge kidney in childhood. AJR 145 315-319... 

Jdquier S, Kaplan BS (1991) Echogenic renal pyramids in children. J Clin Ultrasound 19 85-92 Kamitsuka MD, Peloquin D (1991) Renal calcification after dexamethasone in infants with hronchopulmonary dysplasia (letter). Lancet 337 626... 

Coenzyme Q10 (CoQlO) deficiency. This mitochondrial encephalomyopathy has three main clinical presentations. A predominantly myopathic form is characterized by the triad of exercise intolerance, recurrent myoglobinuria, and CNS involvement. A more frequent ataxic form is dominated by ataxia and cerebellar atrophy, variously associated with weakness, developmental delay, seizures, pyramidal signs, and peripheral neuropathy, often simulating spinocerebellar atrophy. A third presentation with fatal infantile encephalomyopathy and renal involvement, has been described in two families. The biochemical defect (or defects) presumably involve different steps in the biosynthesis of CoQlO, but are still unknown, as are the molecular defects. Diagnosis, however, is important because all patients - and especially those with the myopathic and infantile forms - benefit from CoQlO supplementation [13,14]. 

Dopamine is an intermediate product in the biosynthesis of noradrenaline. Furthermore it is an active transmitter by itself in basal ganglia (caudate nucleus), the nucleus accumbens, the olfactory tubercle, the central nucleus of the amygdala, the median eminence and some areas in the frontal cortex. It is functionally important, for example in the extra-pyramidal system and the central regulation of emesis. In the periphery specific dopamine receptors (Di-receptors) can be found in the upper gastrointestinal tract, in which a reduction of motility is mediated, and on vascular smooth muscle cells of splanchnic and renal arteries. Beside its effect on specific D-receptors, dopamine activates, at higher concentrations, a- and -adrenoceptors as well. Since its clinical profile is different from adrenaline and noradrenaline there are particular indications for dopamine, like situations of circulatory shock with a reduced kidney perfusion. Dopamine can dose-dependently induce nausea, vomiting, tachyarrhythmia and peripheral vasoconstriction. Dopamine can worsen cardiac ischaemia. 

Matsuura M, Kaneman K, Hanai J (1986) Two cases of acute renal failure with loin pain and nausea after exercise, revealing swelling of medullary pyramid on ultrasonography (Japanese abstract). Nippon Jinzo Gakkai Shi (Jpn J Nephrol) 28 1663... 

Before introduction of hemodialysis in the treatment of chronic renal patients, the kidneys of patients who died of Balkan nephropathy used to be the smallest seen at post mortem examinations, weighing 14.8-80 g each (Figure 2A) the difference between the left and right kidneys being small (5-20 g) [74, 76-78]. Surface of the kidneys is smooth, occasionally wavy but never granulated or roughly nodular. The section shows markedly narrowed cortex, pyramid and Bertin s columns are fairly well preserved, and corticomedular border is well differentiated. Papillary necrosis of the pyramids has not been found. 

Among the catecholamines, dopamine has long been of interest to both chemists and neuroscientists. It is one of the most important neurotransmitters and is ubiquitous in the mammalian central nervous system[5]. It modulates many aspects of brain circuitry in a major system of the brain including the extra pyramidal and mesolimbic system, as well as the hypothalamic pituitary axis[6]. It also plays a crucial role in the functioning of the central nervous, cardiovascular, renal and hormonal systems[4], A loss of dopamine containing neurons or its transmission is also related to a number of illnesses and conditions including Parkinson s disease, schizophrenia, motivational habit, reward mechanisms and the regulation of motor functions and in the function of the central nervous, hormonal and cardiovascular system[5,18,19]. It is therefore of interest to measure dopamine in the extracellular fluid in animals to order to monitor neurotransmission processes and correlate neurochemistry with behavior[19]. 

In the kidney, the urate crystals (see Fig. 3-62) are usually in the pyramids as diffuse, pale yellow, chalky deposits. They induce some interstitial inflammation, which may develop into a foreign body granuloma similar to that observed in the soft tissue tophi. The urate accumulation may lead to obstruction of the renal papillae with functional impairment, but usually the development of chronic pyelonephritis is responsible for renal failure. 

A renal lobe is composed of a pyramid and the cortical substance that surrounds it. In some animals, like the pig, these functional lobules are separated anatomically by a fissure. In man, this lobulation exists only during fetal life. 

Quality of the images should be checked prior to the child leaving the department. High-quality images have clear renal outlines, and the pyramids are seen as areas of reduced uptake, while the periphery of the kidney and areas with proximal tubules have higher uptake. Movement will cause blurred or double outlines and loss of the internal differentiation. 

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