Age, geographic, and temporal distribution of fecal shedding of Cryptosporidium parvum oocysts in cow-calf herds.

OBJECTIVE: To evaluate fecal shedding of Cryptosporidium parvum from California cow-calf herds with respect to age, geographic region, temporal effects, and association with watery feces. ANIMALS: Cows and calves from 38 beef cow-calf operations. PROCEDURE: Fecal specimens were collected and examined for C parvum oocysts, using immunofluorescent microscopy. Associations between age, geographic region, month of collection, watery feces, and likelihood of shedding C parvum were evaluated. RESULTS: 3.9% of cattle were shedding C parvum oocysts. Prevalence of shedding among calves ranged from 0 to 13%, and was 0.6% among cattle > or = 12 months old. The odds of shedding C parvum among 2-month-old calves were 41 times greater than among cattle > 4 months old. The odds of shedding C parvum among cattle tested in May were 8.7 times greater than among cattle tested during June, July, or August. The odds of infected individuals having watery feces were 3 to 4 times greater than for noninfected individuals, but the etiologic fraction was only 8 to 9%. CONCLUSIONS AND CLINICAL RELEVANCE: Substantial fecal shedding of C parvum by cow-calf herds was limited to calves 1 to 4 months old, with low prevalence detected in older animals. Risk of contamination of watersheds with C parvum was limited to those periods when young calves were in the herd. Although the odds of having watery feces were greater for animals infected with C parvum than for noninfected animals, the low etiologic fraction suggests that most calves with watery feces were not infected with C parvum.

An unusual site of heterotopic calcification.

Heterotopic calcification may occur following paralysis from spinal cord injury, most commonly affecting the hips. This case demonstrates a bone scan on a T5 paraplegic patient showing an unusual site of heterotopic calcification in the paravertebral musculature in addition to the hip regions. Subsequent CT scanning confirmed the presence of calcification in the erector spinae musculature.

Computed tomography and ultrasound in the diagnosis and treatment of liver abscesses.

Liver abscess remains a serious and even life-threatening condition, despite advances in imaging and treatment. The diagnosis of liver abscess depends heavily on radiologic imaging, particularly ultrasound (US) and computed tomography (CT) scanning. The appearance of liver abscesses on these modalities depends mainly on the chronicity of the abscess. The US and CT features of 33 patients with liver abscesses are presented. Percutaneous drainage of pyogenic abscesses under imaging control is the treatment of choice. Eleven of 24 patients with pyogenic abscesses had percutaneous drainage with good results.

The role of thallium scintigraphy in excluding malignancy in bone.

Scintigraphy with thallium-201 was performed on 22 patients in whom a solitary abnormality in bone was suspected of being malignant. In three patients, an additional lesion was subsequently identified. Preferential TI-201 uptake was found in 7 of 8 malignant lesions, but was absent in 16 of 17 abnormalities that proved to be benign. The use of TI-201 scanning is considered to offer high negative predictive value in the assessment of possible malignant change in bone.

The radiology of cystic liver tumours.

Six patients with cystic liver tumours are presented. The definitive diagnosis of such cystic lesions may be difficult and needle aspiration or biopsy or even operation may be necessary. Clinical and biochemical features may be helpful and in five of the six patients presented, the liver function tests were abnormal. In two patients, diagnostic imaging could not distinguish the tumour from a benign cyst. The differential diagnosis of such cystic liver tumours includes simple cyst, polycystic liver disease, hydatid, liver abscess, haematoma and biloma.

Benign gastric ulcer as a cause of gastrocolic fistula. A report of 3 cases.

Three cases of gastrocolic fistula due to benign gastric ulcer seen during a 5-year period are presented. Although colonic or gastric malignancy is said to be the commonest cause of gastrocolic fistula, in the same period only 1 case due to colonic carcinoma was seen. The important role played by radiology in the diagnosis of gastrocolic fistula is emphasized and the clinical presentation is discussed, together with the possible role of analgesics in the aetiology.

Computed tomography of liver specimens.

Fourteen liver specimens were studied by computed tomography with pathological correlation to evaluate the possible application of this technique to the diagnosis of hepatic lesions. Lesions were clearly demonstrated in 9 of 10 abnormal specimens, but differentiation among hepatomas, metastases, and cysts was not possible in vitro.

The roentgenographic and clinical findings in Whipple's disease. A review of 8 patients.

Out of 8 patients with Whipple's disease, 7 had roentgenographic findings consisting of slight dilatation of the small bowel, with thickening of the mucosal folds. The eighth patient had no abnormality on roentgenographic study. This series represents the first in which the roentgenographic changes have been quantitatively assessed. Confirmation of the diagnosis by biopsy is important because antibiotic treatment results in marked improvement both clinically and roentgenographically.