A careful history and assessment of symptoms will suggest whether a complete or limited examination is indicated and will also help direct the appropriate selection of subsequent diagnostic studies.
EXAMINATION OF THE KIDNEYS
A mass that is visible in the upper abdominal area may be difficult to palpate if soft, as with hydronephrosis. Fullness in the costovertebral angle (CVA) may be consistent with cancer or perinephric infection. The presence and persistence of indentations in the skin from lying on wrinkled sheets suggest edema of the skin secondary to perinephric abscess.
The kidneys lie rather high under the diaphragm and lower ribs and are therefore well protected from injury. Because of the position of the liver, the right kidney is lower than the left. The kidneys are difficult to palpate in men because of (1) resistance from abdominal muscle tone and (2) more fixed position than in women, moving only slightly with change of posture or respiration. The lower part of the right kidney can sometimes be felt, particularly in thin patients, but the left kidney rarely can be felt unless it is enlarged or displaced.
The most successful method of renal palpation is carried out with the patient lying in the supine position on a hard surface (Figure 4–1). The kidney is lifted by one hand in the CVA. On deep inspiration, the kidney moves downward; the other hand is pushed firmly and deeply beneath the costal margin so as to trap the kidney. When successful, the anterior hand can palpate the size, shape, and consistency of the organ as it slips back into its normal position.
Method of palpation of the kidney. The posterior hand lifts the kidney upward. The anterior hand feels for the kidney. The patient then takes a deep breath; this causes the kidney to descend. As the patient inhales, the fingers of the anterior hand are plunged inward at the costal margin. If the kidney is mobile or enlarged, it can be felt between the two hands.
Alternatively, the kidney may be palpated with the examiner standing behind the seated patient. At other times, if the patient is lying on one side, the uppermost kidney drops downward and medially, making it more accessible to palpation. Perlman and Williams (1976) described an effective method of identifying renal anomalies in newborns. The fingers are placed in the CVA, with the thumb anterior and performing the palpation.
An enlarged renal mass suggests compensatory hypertrophy (if the other kidney is absent or atrophic), hydronephrosis, tumor, cyst, or polycystic disease. However, a mass in this area may also represent a retroperitoneal tumor, spleen, lesion of the bowel (eg, tumor, abscess), ...