My intension in this outing was to conclude our brief discussion on acute pancreatitis. This changed with just one phone call. I was called out to issue a death certificate for a young mother of two who died at home. I smelt an opportunity to offer a little advice and some advocacy. Not that there is anything wrong with people dying at home. To the contrary it is the best when the individual is old and didn’t have to bother family members with chronic illness and long period of hospitalization before passing on.
It was so sad that a young lady who had a febrile condition, after having an injection administered to her developed massive cellulitis and died 48hours after the procedure. The injection was given by a Nurse who does home visits and collects stipends for her efforts. This practice in Lagos is commonplace and mainly by auxiliary nurses who tend not to know their limit. This trend is expected to continue as long as the present economic climate continues to prevail.
Now Cellulitis is a bacterial infection involving the inner layer of the skin. This basically is the Dermis and the subcutaneous fat. The basic signs and symptoms is an area of skin that is reddish in color, tender or painful and swollen or oedematous. This area so affected has an ill defined border and tend to spread rapidly in the days ahead. The patient may have a fever associated with rigors or shivering. The areas commonly affected in the body are the legs and face. Other areas of the body can also be affected.
In terms of prevalence, the leg is the commonest site following a break in the skin. The risk factors in this situation would include excessive weight gain or obesity and old age. Cellulitis of the face does not usually result from a break in the skin. As a rule Cellulitis is caused by bacteria penetrating the skin usually by way of a cut or break in the skin and abrasion. Commonly the bacteria involved are the STREPTOCOCCUS and STAPHYLOCOCCUS organisms. These organisms are usually described as being gram-positive. This means that in common haematoylin and eosin staining in the laboratory they absorb the methylene blue stain into their cell wall and appear purple in colour under light microscope.
The main difference between these two organisms is that the streptococcus when dividing is in a linear unidirectional, such that when viewed under light microscope they appear as chains in contrast to the staphylococcal organism which divides in two directions and appears as clusters.
The important thing about these organisms is that they produce preformed toxins that are capable of producing different types of lesions by the same organism. For instance the strept produces the toxin Streptokinase which is involved in the breakdown of blood clots while staphylococcus produces Coagulase which tends to assist in clot formation. The strept and staph sub species and pathogenesis are so numerous and beyond the space available for this outing. But it must be stated that in normal circumstances these bacteria maybe normal flora on the skin without causing any harm.
Now having so, stated the following predisposing factors should be kept in mind when considering cellulitis. These would include insect and animal bites, tattoos which is the current craze worldwide amongst sports personalities and celebrities. Other predisposing factors would include skin rashes, athletes’ foot which is a fungal infection between the toes of the foot and dry skin eczema. Those whose immune system is challenged and the elderly are especially vulnerable to contracting cellulitis.
Diabetic patients deserve special mention with regards to cellulitis. Firstly, their immune system is impaired and secondly there is also impairment of blood circulation in the legs leading to diabetic foot ulcers. Attendant cellulitis in a diabetic patient if not aggressively managed can be life threatening. In some very bad cases it had lead to fatality even after amputation of the affected leg. As a rule any disease condition that affects blood circulation in the leg like varicose veins, Reynolds disease and poor venous flow are all risk factors. We also must be reminded that crowded living conditions like you have in dormitories, military installations, homeless shelters etc. are also risk factors.
The Diagnosis of cellulitis is mainly based on clinical observation and history. Physically, areas of skin swelling, redness and heat are easily identified. The area usually would have been noticed to be rapidly spreading and lymph node close to it may be inflamed. One distinguishing feature with respect to the offending bacteria is the presence of boils or furuncles, carbuncles or abscesses. In some cases there may be a spread of yellowish pyogenic (PUS) membrane on the surface of the lesion. In this instance the offending organism is Staphylococcus aureus. In the case of skin with blisters in which aspiration yielded non purulent fluid, it s assumed that the cellulitis in this instance s caused by the streptococcal organism. This assumption is not diagnostic and not very helpful on making a decision on the line of management.
Having said this much, the presence of abscess, its size and location may require special consideration with respect to the need to have it drained. In challenging circumstances, bed side ultrasound may be used to evaluate certain abscesses especially following the failure of antibiotics therapy. Skin swabs for microbiology study especially where there is skin exfoliation could be done but the results hardly change the line of treatment.
It must be born in mind that there are other conditions that may mimic cellulitis like when blood clot blocks one of the deep veins of the leg, a condition known as deep vein thrombosis and inflammation of the skin due to poor blood flow known as stasis dermatitis. Subcutaneous swelling could be as a result of systemic immunological reaction. The discussion of cellulitis cannot be complete without mentioning Necrotizing fasciitis which is a potentially deadly condition. This infection of body soft tissue which leads to their death or necrosis is caused by a resistant strain of staphylococcus aureus. In this situation, in addition to the symptoms of cellulitis grave signs like vomiting and shock may be present. This condition requires emergency surgery to remove dead tissue a procedure known as wound debridement.
Risk factors associated with this condition include diabetes, alcoholism, drug and substance abuse and peripheral vascular disease. The sites commonly affected in the body are the legs and perineal region. Cellulitis most of the time runs an acute clinical course. If in the event the lesion lasts for more than two weeks other underlying lesion should be looked for.