ClubEnsayos.com - Ensayos de Calidad, Tareas y Monografias
Buscar

Clinica Medica


Enviado por   •  17 de Mayo de 2014  •  1.018 Palabras (5 Páginas)  •  286 Visitas

Página 1 de 5

temperature of 103°F after 3 days of therapy. The urine culture grows

Escherichia coli, which is sensitive to the antibiotics being used. On examina-

tion, he appears ill and has marked left flank tenderness. Ultrasound depicts an

abnormal collection of fluid around the left kidney.

What is the most likely diagnosis?

What anatomical structure is involved?

172 CASE FILES: ANATOMY

ANSWERS TO CASE 25: PERINEPHRIC ABSCESS

Summary: A 55-year-old male continues with high fever and flank pain despite

3 days of broad-spectrum intravenous antibiotic therapy. The urine isolate of

E. coli demonstrates in vitro sensitivity to the antibiotics used. Renal ultra-

sound shows fluid around the left kidney.

Most likely diagnosis: Perinephric abscess

Anatomical structure involved: Kidney and anatomically related

structures

CLINICAL CORRELATION

This 55-year-old male who is suspected of having pyelonephritis is not

improving despite appropriate antibiotic therapy. Pyelonephritis is an infection

of the kidney parenchyma usually caused by an ascending infection of bacte-

ria that advances from the urethra to bladder to ureters and then to the kidney.

Kidney infection usually manifests as fever, flank tenderness, white cells in the

urine, and serum leukocytosis. After 48 to 72 hours, one would expect

decreases in fever and flank tenderness. E. coli is isolated, which is the bac-

terium that most often causes urinary tract infection. The ultrasound examina-

tion is performed to rule out complications of pyelonephritis. The two most

common complications would be a nephrolithiasis or ureterolithiasis (kidney

stone) and perinephric abscess. Intervention is required before improvement is

seen. The abscess must be drained, usually by placement of a percutaneous

catheter under radiologic guidance.

APPROACH TO THE KIDNEYS

Objectives

1. Be able to describe the anatomy of the kidneys, their fascial coverings,

and blood supply.

2. Be aware of the structures next to the kidneys and their relations.

Definitions

Perinephric abscess: Collection of pus in the tissues surrounding the kidney.

Pyelonephritis: Usually a bacterial inflammation of the renal tissue, the

calyces, or renal pelvis.

Nephrolithiasis: Presence of renal calculi or stones.

CLINICAL CASES 173

DISCUSSION

The kidneys are paired retroperitoneal organs that are located in the par-

avertebral gutters. The left kidney lies slightly higher than the right, its

hilum is at the level of L1, and its superior and inferior poles are at the 11th

rib and L3, respectively. The hilum of the right kidney lies at the level of the

disc between L1 and L2, and its inferior pole is nearly 1 to 2 cm superior to

the iliac crest. Each kidney is an encapsulated solid organ, with an outer cor-

tex and an inner medulla, with the latter arranged in renal pyramids. The hilum

of each kidney leads to a space, the renal sinus, which contains fat, branches

of the renal vessels, and the urine-collecting structures (minor and major

calyces and renal pelvis). Within the sinus, the apex of the 6 to 12 renal pyra-

mids is cupped by a minor calyx, which collects the urine produced. Typically

two to three minor calyces unite to form a major calyx, and two to three major

calyces form the renal pelvis. The renal pelvis is continuous with the ureter at

the inferior margin of the hilum (see Case 32 for the anatomy of the ureter).

Four muscles are related to each kidney posteriorly: the diaphragm superi-

orly and the transverses abdominis, quadratus lumborum, and psoas muscles

inferiorly, from lateral to medial. The suprarenal glands and colon contact

both kidneys anteriorly. The duodenum and liver also contact the right

kidney anteriorly, and the stomach, pancreas, and spleen are related to the

anterior left kidney.

Each kidney and suprarenal gland is encased in a renal (Gerota) fascia

(Figure 25-1), which helps to maintain the position of the kidney. The renal fas-

cia fuses with the fascia of the psoas muscle posteriorly and with the adventitia

Inferior vena cava

Aorta

Left renal artery

Left renal vein

True kidney capsule

Peritoneum

Descending colon

Prerenal fascia

Perirenal fat

Pararenal fat

Retrorenal fascia

Suprarenal gland

Separate suprarenal fascia

Fusion of renal fascia

Space of Gerota

Perirenal fat

Peritoneum

Colon

Renal pelvis

Figure 25-1. The left kidney and surrounding fascia. (Reproduced, with per-

mission, from Lindner HH. Clinical Anatomy. East Norwalk, CT:Appleton &

Lange, 1989:444.)

174 CASE FILES: ANATOMY

of the renal vessels anteriorly. Within the renal fascia is an accumulation of fat

known as perirenal fat, which is continuous with the fat within the renal

sinus. Pararenal fat surrounds each kidney external to the renal fascia.

Pararenal fat is thick posterior to the kidney, but thin anteriorly between the

renal fascia and parietal peritoneum.

Each kidney is supplied by a renal artery that arises from the aorta near

vertebral level L2. As each artery nears the renal pelvis, it typically divides

into five segmental arteries that enter the hilum to supply segments of renal tis-

sue. The right renal artery is the longer artery, and both renal arteries lie

posterior to the renal veins when entering the hilum. The renal veins exit the

hilum anterior to the arteries, and the left vein is longer and crosses the mid-

line. Both renal veins drain into the IVC. The left renal vein is unique in

that the inferior phrenic, suprarenal, and gonadal veins drain into it (the

IVC receives these veins on the right side).

COMPREHENSION QUESTIONS

[25.1] During the removal of a patient’s kidney, you would observe which of

the following as being most anterior within the renal sinus?

A. Renal arteries

B. Renal vein

C. Major calyx

D. Minor calyx

E. Renal pelvis

[25.2] You wish to examine the hilum of the right kidney during surgery. Which

of the following structures must be elevated and reflected to do so?

A. Stomach

B. Suprarenal gland

C. Ascending colon

D. Duodenum

E. Liver

[25.3] To elevate the kidney within the renal fascia and the perirenal fat, the

renal fascia must be reflected or incised from the fascia of which of the

following muscles?

A. Diaphragm

B. Psoas muscle

C. Quadratus lumborum muscle

D. Transverses abdominis muscle

E. Iliacus muscle

CLINICAL CASES 175

Answers

[25.1] B. The renal veins lie most anterior within the renal sinus.

[25.2] D. The duodenum lies immediately anteriorly to the hilum of the right

kidney.

[25.3] B. The renal fascia is fused posteriorly to the fascia of the psoas muscle.

ANATOMY PEARLS

The hilum of the left kidney lies at the level of L1.

In the renal sinus, the renal vessels lie anterior to the renal pelvis,

with the renal vein being the most anterior.

The left renal vein receives the inferior phrenic, suprarenal, and

gonadal vessels.

REFERENCES

Moore KL, Dalley AF. Clinically Oriented Anatomy, 5th ed. Baltimore, MD:

Lippincott Williams & Wilkins, 2006:311–17.

Netter FH. Atlas of Human Anatomy, 4th ed. Philadelphia, PA: Saunders, 2006:

plates 329, 332, 342.

Snell RS. Clinical Anatomy by Regions, 8th ed. Baltimore, MD: Lippincott

Williams & Wilkins, 2008:260–5.

...

Descargar como  txt (7.2 Kb)  
Leer 4 páginas más »
txt