Intrathoracic Mycobacterium avium complex infection in immunocompetent children: case report and review.

Mycobacterium avium complex (MAC) infection is a rarely recognized cause of intrathoracic infection in immunocompetent children. The incidence of this disease is unknown but is likely underestimated among children in whom MAC infection is not usually considered. An increase in the number of cases of MAC infection in adults has been noted since the late 1970s. The number of these cases in children with AIDS has also increased. There are currently no guidelines for the treatment of these children. We describe a previously healthy 14-month-old boy with a mediastinal mass for whom tuberculosis was initially diagnosed; subsequently, biopsy-proven infection with MAC was demonstrated. He received no specific therapy after surgical excision of his intrathoracic mass and has done well since. We reviewed eight additional cases of intrathoracic nontuberculous mycobacteria infection in children that were reported from 1979 to 1994 and found excellent outcomes for seven immunocompetent children who received diverse methods of treatment.

Relationship between the pharmacokinetic and pharmacodynamic profile of nilvadipine in the dog.

The purpose of this study was to determine the pharmacokinetic profile of nilvadipine and, using a chronic dog model, determine whether there was a correlation between plasma concentrations of the drug and hemodynamic effects. Nilvadipine was given to four dogs as single intravenous (iv) and oral doses. Pharmacokinetic parameters were estimated after each dose using model-independent methods. The mean elimination half-life was approximately 6 hr after both iv and oral doses. The absolute bioavailability of nilvadipine decreased from 67 to 27% after increasing oral doses (6 and 24 mg), probably because of reduced drug absorption from the gastrointestinal tract. Nilvadipine produced plasma concentration-related decreases in diastolic (DBP) and systolic (SBP) blood pressure and reflex increases in heart rate. The maximum reduction in DBP and SBP ranged from 34 to 53% and 17 to 47%, respectively, from control and was attained at about 0.1 and 0.7 hr after iv and oral doses, respectively. A strong linear correlation between the per cent reduction in both DBP (r = 0.9; p less than 0.001) and SBP (r = 0.66; p less than 0.001) and log plasma concentration of nilvadipine was established. The slopes of the concentration-response relationships were virtually superimposable after both iv and oral routes of administration. A plasma concentration of about 10 and 16 ng/ml was associated with a 14% reduction in DBP or SBP, respectively. There was no clear relationship between plasma concentrations of nilvadipine and changes in heart rate.

Safety assessment of a new anticancer compound, mitoxantrone, in beagle dogs: comparison with doxorubicin. I. Clinical observations.

Twenty-four adult beagle dogs were divided into four groups of three males and three females and received iv infusions of doxorubicin (36.05 mg/m2), mitoxantrone (2.58 or 5.15 mg/m2), or the vehicle (0.9% normal saline). All animals were given a single dose once every 3 weeks. The duration of the study was 30 weeks. Animals were observed for toxicologic and cardiotoxic signs. The methods used to evaluate the cardiotoxic potential of both mitoxantrone and doxorubicin were sequential endomyocardial biopsies, ECGs, blood pressure, and serum levels of the cardiospecific isoenzyme CPK-MB (MB band of CPK). Animals given mitoxantrone had signs of gastrointestinal toxicity and fluctuating decreases in wbc counts. Animals given doxorubicin had signs of gastrointestinal toxicity and cardiotoxicity, as well as alopecia, fluctuating decreases in wbc counts, and diffuse erythema. All three male animals given doxorubicin died during the study from apparent congestive heart failure. All dogs treated with doxorubicin had positive CPK isoenzyme elevation, ECG changes, or progressive cardiomyopathy prior to administration of the last dose. None of these signs was observed in dogs treated with mitoxantrone. One male dog given mitoxantrone died during the course of the study.

Endomyocardial biopsy in the dog.

A technique for transvenous endomyocardial biopsy of the right ventricular septum was modified from an existing procedure described in man and was applied in the dog. More than 120 procedures were performed in 36 dogs. One dog died, but lesions noticed at necropsy were not sufficient to establish the specific cause of death. Other fatalities or major complications were not encountered.

Acute copper toxicosis in the Canada goose.

Acute copper toxicosis resulted in Canada geese, Branta canadensis, following ingestion of copper sulfate at about 600mg/kg from a small man-made pond on a game farm. The lesions were those associated with copper toxicosis in other avian species. The primary pathologic change was necrosis and sloughing of the proventriculus and gizzard. A greenish discoloration of the lungs also occurred.

Febrile seizures in children.

Benign febrile convulsions occur early in the course of fever of extracranial origin in children six months to five years old. The first seizure always calls for a spinal tap to exclude meningitis, as well as appropriate studies to exclude other causes of seizure activity. An EEG one week later is indicated but more extensive studies are usually nonproductive. The question of whether to employ long-term phenobarbital therapy has not been resolved.