Nocardia Keratitis: A Case Report

Purpose

To describe a case of Nocardia keratitis resistant to 2% amikacin, with a toxic-allergic reaction to fortified topical 5% amikacin, and recurrence of the infection with topical corticosteroids.

Methods

Nocardia was diagnosed from a smear and positive culture and identified as Nocardia asteroides by gas chromatography and quantitative fatty acid analysis using the Microbial Identification System. Treatment was started with topical 2% amikacin, which was subsequently raised to 5% because of clinical resistance.

Results

A toxic-allergic reaction was observed after 5% amikacin so the drug was discontinued and commercially available drugs combining 1% chloramphenicol, 0.5% tetracycline, and 18 mil IU colistin with 0.3% ofloxacin were given. These were well tolerated and the infection improved quickly. After 1 month the antibiotics were discontinued and topical 0.1% clobetasone was given to reduce scar formation. The infection recurred after 1 week but responded to 3 months of the previous antibiotic combination and its sensitivity was checked with the Epsilometer test.

Conclusions

Nocardia keratitis may not respond to 2% topical amikacin and fortified topical 5% amikacin may cause a strong toxic-allergic reaction. A commercially available combination of chloramphenicol, tetracycline, and colistin, with ofloxacin, may be effective but the treatment must be continued for several months. Topical steroids should only be used with considerable caution since they can lead to relapse of the infection.

Nocardia keratitis: A case report

PURPOSE

To describe a case of Nocardia keratitis resistant to 2% amikacin, with a toxic-allergic reaction to fortified topical 5% amikacin, and recurrence of the infection with topical corticosteroids.

METHODS

Nocardia was diagnosed from a smear and positive culture and identified as Nocardia asteroides by gas chromatography and quantitative fatty acid analysis using the Microbial Identification System. Treatment was started with topical 2% amikacin, which was subsequently raised to 5% because of clinical resistance.

RESULTS

A toxic-allergic reaction was observed after 5% amikacin so the drug was discontinued and commercially available drugs combining 1% chloramphenicol, 0.5% tetracycline, and 18 mil IU colistin with 0.3% ofloxacin were given. These were well tolerated and the infection improved quickly. After 1 month the antibiotics were discontinued and topical 0.1% clobetasone was given to reduce scar formation. The infection recurred after 1 week but responded to 3 months of the previous antibiotic combination and its sensitivity was checked with the Epsilometer test.

CONCLUSIONS

Nocardia keratitis may not respond to 2% topical amikacin and fortified topical 5% amikacin may cause a strong toxic-allergic reaction. A commercially available combination of chloramphenicol, tetracycline, and colistin, with ofloxacin, may be effective but the treatment must be continued for several months. Topical steroids should only be used with considerable caution since they can lead to relapse of the infection. (Eur J Ophthalmol 2006; 16: 164-7).

Bilateral Acanthamoeba keratitis with late recurrence of the infection in a corneal graft: a case report

PURPOSE

To report a case of bilateral Acanthamoeba keratitis with late, atypical recurrence after penetrating keratoplasty a chaud.

METHODS

A 23-year-old contact lens wearer was treated for bilateral Acanthamoeba keratitis and underwent penetrating keratoplasty in the right eye for descemetocele with impending risk of perforation. The postoperative course was uneventful and topical steroids were combined with neomycin and propamidine. Two months after the operation in the right eye the patient presented with active infection in the left eye. One month later recurrence appeared in the right eye, as a central corneal infiltrate in the graft.

RESULTS

Recurrences in both eyes were successfully treated with a combination of hexamidine and neomycin, and with polyhexamethylene biguanide respectively. The right eye was regrafted three months after the recurrence and penetrating keratoplasty was done two years later in the left eye. Both grafts were successful and remained clear. There has been no further recurrence in the long-term follow-up.

CONCLUSIONS

Recurrence of Acanthamoeba keratitis after penetrating keratoplasty a chaud may occur even several months after the operation and the manifestation may be atypical. Current antiamoebal therapy was effective and regrafting in the quiet eye was successful.

[Systemic and pulmonary vascular resistance in brain death]

BACKGROUND

Hemodynamic instability is known to affect brain dead subjects and it can be dangerous for the viability of transplantable organs. Aim of the present study was to assess the hemodynamic performance in brain dead subjects, the changes during the legal observation period and the results of therapeutic management.

METHODS

The authors evaluated 28 consecutive adult brain dead subjects, all in intensive treatment, controlled ventilation, infusion therapy and/or dopamine administration and continuous direct monitoring of arterial pressure. Ten hemodynamic parameters have been registered by the thermodilution method and the Swann-Ganz catheter. The Legal Committee performed measurements at the beginning (T0) and the end (T6) of the observation period, which lasts 6 hours according to the current law on death certification (Law N. 578/93).

RESULTS

Low systemic and pulmonary vascular resistances have been documented in the majority of subjects (75%), both treated only with fluids and with the additional dopamine administration (dosage lower than 10 ug/Kg/min). The above-mentioned reduction was similar at the two different monitored times (T0 and T6).

CONCLUSIONS

This situation can be ascribed to the destruction of the cerebral vasoactive centers and the consequent hypotension is due to autonomic nervous system dysfunction. Hemodynamic instability must be treated by fluids and inotropic drugs, but they may cause cardiac and respiratory problems, thus it is suggested to use also low doses of vasoconstrictive drugs, provided that cardiac condition allows this therapeutic strategy.

[Tracheal intubation: increase of arterial pressure and cerebral blood flow velocity. Effect of thiopentone and propofol]

Induction of anaesthesia in intracranial surgery, especially for vascular diseases, must minimize haemodynamic changes: blood pressure and cerebral blood flow must not be increased to a high degree. Our work compares increases in blood pressure and in the speed of cerebral blood flow during endotracheal intubation in two groups of patients, who received propofol or thiopentone for the induction of anaesthesia. We studied 30 patients, without intracranial diseases, who underwent lumbar slipped disk surgery. Half of the patients received thiopentone and curare before intubation and the other half propofol and curare. Increase in blood pressure after intubation was lower with propofol than with thiopentone in a statistically significant way. Also the increase in the speed of cerebral blood flow, measured with doppler technique, was lower when induction with propofol was used, though not statistically relevant.

[Infective complications of external ventricular shunts]

Since the sixties at our Department of Neurosurgery, we use an original method for external ventricular shunts. To verify the effectiveness for reduction of infections risks the Authors have retrospectively analyzed 95 patients: only 4 cases of meningitis have been observed. The Authors consider the utility of the proper method and the importance of the duration of ventriculostomy placement.

[Cerebral pathology and hyponatremia. Cerebral damage with central pontine myelinolysis after rapid correction]

Hyponatremia is a state of relatively common observation among neurosurgical patients and it may determine or precipitate a condition of brain swelling in the head-injured. The quick reversal to normal values of serum sodium concentration may cause relevant neurological disturbances: they are related to peculiar neuropathological changes, the most representative of which is central pontine myelonilysis. Two cases (one in pediatric age) of head injured patients with brain damage resulting from rapid correction of a SIADH related hyponatremia are presented.