Loiasis in an expatriate American child: diagnostic and treatment difficulties.

On the basis of this experience, we recommend the following when faced with possible filariasis in an expatriate from Western Central Africa: (1) Attempt a clinical differentiation between L loa and other filarial infections present in West Africa. It is important to suspect loiasis because this is the only filarial infection that is readily curable; (2) ophthalmologic assessment to diagnose onchocerciasis; (3) if L loa is suspected, thick blood smears should be obtained from midmorning to midafternoon and stained with Giemsa or hematoxylin stains, after a concentration technique is used. Nighttime blood specimens should be obtained if the patient has been in an area where W. bancrofti is prevalent; (4) skin snip biopsies prepared as follows: Bilateral symmetrical skin snips should be taken. In the case of suspected West African filariasis, the pelvic girdle, iliac crest, and back of scapula are thought to have the highest yield. One snip from each of six different sites should be obtained. Each skin snip should be approximately 2 to 3 mm (a cornealoscleral biopsy forceps can be used). Each skin snip is placed in 100 microL (approximately one drop) of normal saline in a flat-bottomed microtiter plate. The plate is incubated at room temperature and checked periodically for 24 hours under a dissecting microscope (X20 to X40). If present, the small worms will be seen wiggling and squirming in the drop of saline; (5) serologic diagnostic methods are most efficient if human filarial antigens are used; (6) if treatment is with diethylcarbamazine, the initial dose should be small.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of observed sudden infant death syndrome (SIDS) on hospital staff.

We have described an observed case of SIDS in a hospital setting. The victim was "well baby" hospitalized for psychosocial reasons. Death occurred on the fifth hospital day, during sleep and two hours after feeding. The death was silent and was preceded by cyanosis and respiratory arrest. Hospital staff who attended the baby during his admission experienced the same traumatic reactions as families of SIDS victims, ie, shock, disbelief, anger, guilt, fear, blaming, sadness, and behavioral manifestations. Information on SIDS, communication about feelings and continued group support were of utmost importance in helping the staff to deal with the crisis. Although they had experienced death and serious illness on the ward and continued to be faced with grave situations, the unique aspects of SIDS, namely lack of etiology and its sudden and unexpected onset, brought forth personal feelings of vulnerability and called for extra coping devices. Our experience illustrates the need of an in-hospital support system to assess needs, coordinate efforts, and offer timely intervention after the death of an infant or child.

Ectopic immature renal tissue over the dorsum of lumbar and sacral area in two infants.

During reparative surgery for meningomyelocele of the lumbar area, a 7-week-old female infant was found to have a small, well-delineated, subcutaneous, renal blastema. A 3-month-old female infant was found to have immature renal tissue, consisting of glomeruli and tubules, in a soft tissue swelling dorsal to the sacrum. Neither of these patients showed neurologic or renal abnormalities. The second patient has had a disease-free follow-up period of six years. The possible etiology and significance of these benign findings and their relation to the origin of Wilms tumors are discussed.

Limb body-wall complex in association with sirenomelia sequence.

Limb body-wall complex and sirenomelia sequence are uncommon birth defects and their association is extremely rare. Their overlapping manifestations and their concurrence in our patient suggest that they share a common cause and belong to a group of pathologically closely related conditions. Embryonic vascular disruption may be a common pathogenesis in both anomalies.

Homozygous achondroplasia with survival beyond infancy.

Homozygous achondroplasia has been thought to be uniformly lethal in the neonatal period. We describe three children, born to achondroplastic parents, who were homozygous for this disorder but who survived beyond early infancy. Two died suddenly at 37 and 33 mo; the third survives at 29 wk. At least in some instances aggressive treatment may allow others with this condition to survive with a reasonable quality of life.

Oncocytic cardiomyopathy syndrome.

The case presented is the first report of oncocytic cardiomyopathy associated with congenital heart disease. The clinical presentation was typical of hypoplastic left heart syndrome, and the oncocytic cardiomyopathy was an unexpected finding at autopsy. The associated lesions of oncocytic metaplasia in thyroid and pituitary gland have been previously reported. Maternal serology and viral cultures from the infant were negative, indicating that the oncocytic lesions were not secondary to congenital viral infection. We support the theory that oncocytic cardiomyopathy is a hamartomatous lesion, and propose as a paradigm the association between cardiac rhabdomyoma and tuberous sclerosis. Careful follow-up of surgically "cured" oncocytic cardiomyopathy should uncover oncocytomas in other organs later in life.

Fetal infection with human parvovirus B19.

The case of premature infant with nonimmune hydrops secondary to human parvovirus B19 infection is presented. The infection was not suspected clinically. The fetal autopsy showed intranuclear inclusions in erythroid cells that stained positively with a DNA hybridization probe for B19 parvovirus.

Vascular ring in interruption of the aortic arch with bilateral patent ductus arteriosi.

The previously unreported occurrence of a true vascular ring in association with interruption of the aortic arch resulting from bilateral persistence of the ductus arteriosi is described. Division of both ductus is necessary to minimize the potential for tracheobronchial compression. This should be accomplished either during definitive (one-stage) repair of the interrupted aortic arch and associated anomalies or at the initial procedure of a staged repair.

Mortality after carotid body denervation in rats.

Carotid body denervation (CBD) in neonatal goats and piglets results in minimal irregular breathing and no fatalities. Redundancy and/or plasticity of peripheral chemosensitivity and a relatively mature ventilatory control system at birth may contribute to the paucity of CBD effects in these species. In the present study, we tested the hypothesis that CBD mortality would be greater in neonates of a less mature species such as the rat. We found that the mortality in rats denervated at 2-3 and 7-8 days of age was significantly higher (P < 0.05) than in sham-CBD rats. In all surviving rats, pulmonary ventilation during hypoxia was lower in CBD than in sham operated rats 2 days after denervation. In surviving rats denervated during the 7th and 8th postnatal days, there was also reduced weight gain and pulmonary ventilation during eupnea, including apneas up to 20 s in duration. However, the effects of CBD were compensated within 3 wk after denervation. Local injections of NaCN indicated that aortic chemoreceptors might have been one of the sites of recovery of peripheral chemosensitivity. We concluded that CBD has higher mortality in newborn rats than in other mammals, possibly because of the relative immaturity of these animals at birth. Nonetheless, in survivors there was enough redundancy and plasticity in the control of breathing to eventually compensate for the consequences of CBD.

Effects of carotid and aortic chemoreceptor denervation in newborn piglets.

The objective of the present study was to test the hypothesis that in neonatal piglets there would be no hypoventilation after sham denervation or aortic denervation (AOD) alone, but there would be transient hypoventilation after carotid body denervation (CBD) and the hypoventilation would be greatest after combined carotid and aortic denervation (CBD+AOD). There was a significant (P < 0.05) hypoventilation in CBD and CBD+AOD piglets denervated at 5, 15, and 25 days of age. The hypoventilation in CBD+AOD piglets denervated at 5 days of age was greater (P < 0.05) than that of all other groups. Conversely, sham-denervated and AOD piglets did not hypoventilate after denervation. Injections of sodium cyanide showed that aortic chemoreceptors were a site of recovery of peripheral chemosensitivity after CBD. This aortic sodium cyanide response was abolished by prior injection of a serotonin 5a receptor blocker. Residual peripheral chemosensitivity after CBD+AOD was localized to the left ventricle. We conclude that 1) aortic chemoreceptors contribute to eupneic breathing in piglets that were carotid denervated at 5 days of age and 2) there are multiple sites of residual peripheral chemosensitivity after CBD.

Effect on breathing of ventral medullary surface cooling in neonatal goats.

The present study was designed to determine whether neurons near the ventral medullary surface (VMS) that are important to control of breathing in adult mammals are also important to control of breathing in neonates. In 7-day-old goats (n = 22), the VMS was surgically exposed under halothane anesthesia. Stainless steel thermodes (2 x 2 mm) were used to cool (20 degrees C) and thereby create neuronal dysfunction of discrete VMS sites. Bilateral cooling under anesthesia 0-2 or 2-4 mm lateral to the midline between the exit of cranial nerves VI and XII resulted in a reduction (P < 0.05) of breathing and most often in apnea. Cooling caudal or rostral to this area did not have a consistent effect on breathing. In 7-day-old goats (n = 8), 3 x 3-mm thermodes were chronically implanted bilaterally on the VMS surface between the exit of cranial nerves VI and XII. The goats recovered and were studied over several days thereafter. VMS cooling while the goats were awake caused breathing to decrease (P < 0.05), but apnea was never observed. The decrease was less (P < 0.05) than while the goats were anesthetized. After 10 s of cooling, the hypopnea while the goats were awake was uniform during eupnea, hypercapnia, hyperoxia, and hypoxia, but after 10 s of cooling, the decrease was relatively greater (P < 0.05) during hyperoxia and hypercapnia. These effects of VMS cooling are qualitatively the same as in adult goats; thus the data are consistent with mature VMS contribution to the control of breathing in neonatal goats.

Effect of carotid body denervation on breathing in neonatal goats.

The objective of the present study was to determine in goats whether carotid body denervation (CBD) at 1-3 days of age causes permanent changes in breathing greater than those that occur after CBD in adult goats. Goats underwent CBD (n = 6) or sham CBD (n = 3) surgery at 1-3 days of age. In addition, one unoperated control animal was studied. Bolus intravenous injections of NaCN 2 days postsurgery verified successful CBD surgery. However, at 3, 11, and 18 mo of age, the CBD goats had regained a NaCN response that did not differ (P > 0.10) from that of intact goats. Intracarotid NaCN injections elicited a hyperpnea in the sham CBD but not the CBD goats. Only one animal exhibited highly irregular breathing [characterized by prolonged (>9-s) apneas] after CBD, and the irregularity disappeared by 3 mo of age. One CBD goat died at 35 days of age, and autopsy revealed that death was associated with pneumonia. After 3 mo of age, there were no statistically significant differences (P > 0.10) between sham and CBD goats in eupneic breathing, hypoxia and CO(2) sensitivity, and the exercise hyperpnea. It is, therefore, concluded that CBD at 1-3 days of age in goats does not appear to affect selected aspects of respiratory control after 3 mo of age, conceivably because of the emergence of other functional chemoreceptors that compensate for the loss of the carotid chemoreceptor.

Effects on breathing of carotid body denervation in neonatal piglets.

The purpose of these studies was to test the hypothesis that carotid chemoreceptor activity is necessary for postnatal maturation of the ventilatory control system. By using a lateral surgical access, 17 piglets were carotid body denervated (CBD) and 14 were sham denervated at 3-25 days of age. After surgery, there was no irregular breathing in any group. There was no significant hypoventilation when CBD was performed at less than 5 days of age (n = 5) and only a mild (arterial PCO(2) 5 Torr; P < 0.05) to moderate, transient (arterial PCO(2) 8 Torr; P < 0.5) hypoventilation in piglets denervated at 10-15 (n = 6) and 20-25 (n = 6) days of age, respectively. Three weeks after surgery, both breathing of a hypoxic gas mixture and jugular venous NaCN injections elicited a hyperpnea in the CBD piglets that was attenuated compared with that in sham CBD piglets. In the CBD piglets, there was no response to injections of NaCN in the carotid arteries, but there was a response to NaCN injected into the proximal descending aorta, suggesting the residual peripheral chemosensitivity was of aortic origin. Carotid chemoreceptor-intact piglets had carotid and aortic NaCN chemosensitivity by 2 days of age. The carotid response persisted for the 40 days of the study, but the aortic reflex persisted only until approximately 8 days of age. We conclude that 1) the major effect of CBD per se in neonatal piglets is age-dependent hypoventilation and 2) there is a high degree of plasticity in peripheral chemosensitivity in neonates that may contribute to minimizing the changes in breathing after CBD.

Serotonin and serotonin receptor expression in the aorta of carotid intact and denervated newborns.

Pharmacological blocking of serotonin (5-HT) 5A receptors abolishes aortic ventilatory chemosensitivity of carotid body denervated (CBD) piglets [J. Appl. Physiol. 92 (2002) 893]. Accordingly, the purpose of the present study was to determine whether 5-HT and 5-HT receptors exist at aortic sites that are chemosensitive after CBD. Aortas from CBD and sham CBD rats and piglets and from aortic denervated (AOD) and combined AOD+CBD piglets were harvested, sectioned and then studied using immunohistochemistry and western blot techniques. 5-HT immunoreactivity in piglets and rats was concentrated in the endothelium and sub-endothelial areas in several aortic regions studied, and in some areas also in the adventitia. At the aortic chemosensitive site (descending aorta in CBD piglets and the ascending aorta in CBD rats), the immunoreactivity was greater (P < 0.05) than in other aortic regions and greater than in other groups studied. The 5-HT(5a) receptor was expressed only at the chemosensitive sites and only in aortic innervated piglets. We conclude that the data from this and a previous study [J. Appl. Physiol. 92 (2002) 893] suggest that a serotonergic mechanism contributes to the aortic ventilatory chemoreflex after CBD.

Rapid quantitation of hemoglobin S by isoelectric focusing.

The feasibility of isoelectric focusing (IEF) to determine hemoglobin S (HbS) at a faster turn-around-time and to resolve the HbS and hemoglobin A (HbA) in presence of high concentrations of hemoglobin F (HbF) is evaluated. The IEF procedure is faster, and the results can be obtained in less than 45 minutes. The resulting data are comparable to gel electrophoresis. It is a superior procedure in resolving both HbS and HbA in the presence of high HbF and, therefore, a desirable technique to use for infants and children. Further, IEF is simpler than the gel electrophoresis, relatively inexpensive, easily adaptable for routine use, and suitable for "stat" conditions.

Placental pathology casebook. Chorangiosis of the placenta increases the probability of perinatal mortality.

Two apparent acute problems that may occur in labor, nuchal cord and placental abruption, were associated with chorangiosis of the placenta. The importance of complete placental examination in perinatal mortality is re-emphasized. The association of apparent acute obstetrical conditions, e.g., nuchal cord and placental abruption with chorangiosis of the placenta, may be the cause of fetal-newborn deaths that were previously assumed to be issues of labor management.

A hypothesis: sudden infant death syndrome is a disorder of entrainment.

A hypothesis is presented that explains Sudden Infant Death Syndrome (SIDS) as a disorder of entrainment. This hypothesis fits the known characteristics of SIDS i.e., age at death, sleep-related, natural death and absence of a lethal lesion. The spectrum from reversible hypoxia (near-miss SIDS) to irreversible hypoxia (SIDS) can be explained by the presence or absence of brainstem lesions in infants with a disorder of entrainment.

A study of the endogenous opioid system in the sudden infant death syndrome.

To investigate the possible role of the endogenous opioid system in the pathogenesis of the sudden infant death syndrome (SIDS), we measured met-enkephalin immunoreactivity by radioimmunoassay in brain, lung, and adrenal glands of SIDS victims and of infants (controls) dying of nonneurologic causes. Met-enkephalin was stable in brain tissue up to 24 hours after death. On inspection, met-enkephalin levels in the cerebral cortex of SIDS victims were similar to those in controls. Levels in the caudate nucleus were lower in infants than in adults. In the medulla, the levels in SIDS cases and controls were not found to differ significantly. The linear relationship between the levels in the medulla and age was not detectably different in SIDS and controls. However, as a subset, levels in the control group significantly decreased with increasing age (P = 0.005), whereas levels in the SIDS group showed no correlation with age (P = 0.33). Levels of met-enkephalin in the adrenal gland of SIDS victims were similar to those in controls and were considerably lower than adult values. Lung tissue was assayed for beta-endorphin immunoreactivity and met-enkephalin: for both peptides the values in SIDS cases were low (femtomolar range) and similar to those in controls. These data suggest that met-enkephalin is not markedly overproduced in brains of SIDS victims. Future postmortem studies should focus on more subtle evidence of endogenous opioid overactivity such as differences in age related changes, receptor number, and levels of other endogenous opioid peptides.

Angiomatous malformation of the testis in an infant.

A 2-mo-old infant with a benign vascular lesion of the right testis and epididymus was presented. The lesion was diagnosed by incisional biopsy avoiding orchiectomy. One year later, the lesion has not increased in size. A careful follow-up of patients with these rare lesions is required to increase our knowledge about the pathogenesis.